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Free PDF Download of CBSE Physics Multiple Choice Questions for Class 12 with Answers Chapter 11 Dual Nature of Radiation and Matter. Physics MCQs for Class 12 Chapter Wise with Answers PDF Download was Prepared Based on Latest Exam Pattern. Students can solve NCERT Class 12 Physics Dual Nature of Radiation and Matter MCQs Pdf with Answers to know their preparation level.

Dual Nature of Radiation and Matter Class 12 Physics MCQs Pdf

Dual Nature of Radiation and Matter MCQ Questions with Answers Pdf Question 1. Light of frequency 1.9 times the threshold frequency is incident on a photosensitive material. If the frequency is halved and intensity is doubled, the photocurrent becomes
(a) quadrupled
(b) doubled
(c) halved
(d) zero

Answer/Explanation

Answer: d
Explaination: (d) As v_i = 0.95 v₀. No photoelectric emission takes place.

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Dual Nature of Matter And Radiation Class 12 MCQ Question 2. Threshold wavelength for a metal having work function W0 is X. What is the threshold wavelength for the metal having work function 2W0?
(a) 4λ
(b) 2λ
(c) λ/2
(d) λ/4

Answer/Explanation

Answer: c
Explaination:

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MCQ on Dual Nature of Matter And Radiation Question 3. Radiations of frequency v are incident on a photosensitive metal. The maximum K.E. of the photoelectrons is E. When the frequency of the incident radiation is doubled, what is the maximum kinetic energy of the photoelectrons?
(a) 2E
(b) 4E
(c) E + hv
(d) E – hv

Answer/Explanation

Answer: c
Explaination: (c) Using Einstein’s photoelectric equation hv – w₀ = E

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4. Maximum kinetic energy (E_k) of a photoelectron varies with frequency (v) of the incident radiation as

Answer/Explanation

Answer: d
Explaination: (d) Using Einstein’s photoelectric equation hv = hv₀ + E_k

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Physics MCQs for Class 11 With Answers Pdf Question 5. The stopping potential V₀ for photoelectric emission from a metal surface is plotted along y-axis and frequency v of incident light along x-axis. A straight line is obtained as shown. Planck’s constant is given by

(a) slope of the line
(b) product of the slope of the line and charge on electron
(c) intercept along y-axis divided by charge on the electron
(d) product of the intercept along x-axis and mass of the electron

Answer/Explanation

Answer: b
Explaination: (b) Using Einstein’s photoelectric equation

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6. The energy of photon of wavelength 450 nm is
(a) 2.5 × 10^-17 J
(b) 1.25 × 10^-17 J
(c) 4.4 × 10^-19 J
(d) 2.5 × 10^-19 J

Answer/Explanation

Answer: c
Explaination:

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7. The kinetic energy of an electron is 5 eV. Calculate the de broglie wavelength associated with it. (h = 6.6 × 10^-34 Js, m_e = 9.1 × 10^-31 kg)
(a) 5.47 Å
(b) 10.9 Å
(c) 2.7 Å
(d) None of these

Answer/Explanation

Answer: c
Explaination:

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Photoelectric Effect Multiple Choice Questions and Answers Pdf8. The slope of the stopping potential versus ‘ frequency graph for photoelectric effect is equal to

(a) h
(b) he
(c) h/e
(d) e

Answer/Explanation

Answer: c
Explaination:
(c) Using Einstein’s equation for photoelectric effect

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Class 12 Physics MCQ Chapter Wise Question 9. A proton and an α-particle are accelerated by the same potential difference. The ratio of their de broglie wavelengths (λ_p, λ_α) is
(a) 1
(b) 2
(c) √8
(d) \(\frac{1}{\sqrt{8}}\)

Answer/Explanation

Answer: c
Explaination:

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Class 12 Physics MCQ Chapter Wise Question 10. Work function of three metals A, B and C are 4.5 eV, 4.3 eV and 3.5 eV respectively. If a light of wavelength 4000 Å is incident on the metals then
(a) photoelectrons are emitted from A.
(b) photoelectrons are emitted from B.
(c) photoelectrons are emitted from C.
(d) photoelectrons are emitted from all the metals.

Answer/Explanation

Answer: d
Explaination:
(d) Since energy of incident photon

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11. Which of the following figure represents the variation of particle momentum and associated de Broglie wavelength?

Answer/Explanation

Answer: d
Explaination:

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12. According to Einstein’s photoelectric equation the plot of the kinetic energy of the emitted photo-electrons from a metal vs the frequency of the incident radiation gives a straight line whose slope
(a) depends on the nature of the metal used.
(b) depends on the intensity of the radiation.
(c) depends both on the intensity of the radiation and the metal used.
(d) is the same for all metals and independent of the intensity of the radiation.

Answer/Explanation

Answer: d
Explaination: (d) Since slope = \(\frac{h}{e}\)

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13. If K.E. of free electron is doubled, its de Broglie wavelength will change by factor
(a) \(\frac{1}{\sqrt{8}}\)
(b) √2
(c) \(\frac{1}{2}\)
(d) 2

Answer/Explanation

Answer: a
Explaination:

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14. For a given kinetic energy which of the following has smallest de Broglie wavelength?
(a) Electron
(b) Proton
(c) Deutron
(d) a-particle

Answer/Explanation

Answer: d
Explaination:
(d) Since de Broglie wavelength

particle, mass of ∝-particle is maximum.

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15. A particle is dropped from a height H. The de Broglie wavelength of the particle as a function of height is proportional to [NCERT Exemplar]

Answer/Explanation

Answer: d
Explaination:

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16. A proton, a neutron, an electron and an a-particle have same energy. Then their de Broglie wavelengths compare as [NCERT Exemplar]
(a)λ_p = λ_n > λ_e > λ_α
(b) λ_α < λ_p = λ_n < λ_e
(‘C) λ_e < λ_p = λ_n > λ_α
(d) λ_e = λ_p = λ_n = λ_α

Answer/Explanation

Answer: b
Explaination:

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17. In photoelectric effect what determines the maximum velocity of electron reacting the collector?
(a) Frequency of incident radiation alone
(b) Work function of metal
(c) Potential difference between the emitter and the collector
(d) All of these

Answer/Explanation

Answer: d
Explaination: (d) As per Einstein’s photoelectric equation

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18. A Proton and an a-particle have the same de Broglie wavelength. What is same for both of them?
(a) Mass
(b) Energy
(c) Frequency
(d) Momentum

Answer/Explanation

Answer: d
Explaination: (d) Since λ = \(\frac{h}{p}\), for the same wavelength momentum is also same.

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19. The wavelength of a photon needed to remove a proton from a nucleus which is bound to the nucleus with 1 MeV energy is nearly [NCERT Exemplar]
(a) 1.2 nm
(b) 1.2 × 10^-3 nm
(c) 1.2 × 10^-6 nm
(d) 1.2 × 10¹ nm

Answer/Explanation

Answer: b
Explaination:

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20. An electron is moving with an initial velocity v = v0i and is in a magnetic field B = B0 j. Then, its de Broglie wavelength [NCERT Exemplar]
(a) remains constant.
(b) increases with time.
(c) decreases with time.
(d) increases and decreases periodically.

Answer/Explanation

Answer: a
Explaination:
(a) F = q(v × B) = F = qvB sin θ. As this force is perpendicular to v and B, so the magnitude of v will not change, i.e. momentum (p = mv) will remain constant in magnitude
De Broglie wavelength λ = \(\frac{h}{m v}\) remams constant
∴ Comparing wavelengths of proton and neutron, m_p = m_n, hence λ_p = λ_n.

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21. Who established that electric charge is quantised?
(a) J.J. Thomson
(b) William Crookes
(c) R.A. Millikan
(d) Wilhelm Rontgen

Answer

Answer: c

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22. Cathode rays were discovered by
(a) Maxwell Clerk James
(b) Heinrich Hertz
(c) William Crookes
(d) J.J. Thomson

Answer

Answer: c

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23. The minimum energy required for the electron emission from the metal surface can be supplied to the free electrons by which of the following physical processes?
(a) Thermionic emission
(b) Field emission
(c) Photoelectric emission
(d) All of these

Answer

Answer: d

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24. The phenomenon of photoelectric emission was discovered in 1887 by
(a) Albert Einstein
(b) Heinrich Hertz
(c) Wilhelm Hallwachs
(d) Philipp Lenard

Answer

Answer: b

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25. A metal surface ejects electrons when hit by green light but nothing when hit by yellow light. The electrons will be ejected when the surface is hit by
(a) blue light
(b) heat rays
(c) infrared light
(d) red light

Answer

Answer: a

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26. Which of the following statements is correct regarding the photoelectric experiment?
(a) The photocurrent increases with intensity of light.
(b) Stopping potential increases with increase in intensity of incident light.
(c) The photocurrent increases with increase in frequency.
(d) All of these

Answer

Answer: a

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27. In photoelectric effect, the photocurrent
(a) depends both on intensity and frequency of the incident light.
(b) does not depend on the frequency of incident light but depends on the intensity of the inci-dent light.
(c) decreases with increase in frequency of inci-dent light.
(d) increases with increase in frequency of inci-dent light.

Answer

Answer: b

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28. The maximum value of photoelectric current is called
(a) base current
(b) saturation current
(c) collector current
(d) emitter current

Answer

Answer: b

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29. In photoelectric effect, the photoelectric current is independent of
(a) intensity of incident light
(b) potential difference applied between the two electrodes
(c) the nature of emitter material
(d) frequency of incident light

Answer

Answer: d

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30. In photoelectric effect, stopping potential depends on
(a) frequency of incident light
(b) nature of the emitter material
(c) intensity of incident light
(d) both (a) and (b)

Answer

Answer: d

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31. According to Einstein’s photoelectric equation, the graph of kinetic energy of the photoelectron emitted from the metal versus the frequency of the incident radiation gives a straight line graph, whose slope
(a) depends on the intensity of the incident radi-ation.
(b) depends on the nature of the metal and also on the intensity of incident radiation.
(c) is same for all metals and independent of the intensity of the incident radiation.
(d) depends on the nature of the metal.

Answer

Answer: c

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32. The figure shows stopping V0A potential V0 and frequency o for two different metallic surfaces A and B. The work function of A, as compared to that of B is

(a) less
(b) more
(c) equal
(d) nothing can be said

Answer

Answer: a

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33. Which phenomenon best supports the theory that matter has a wave nature?
(a) Electron momentum
(b) Electron diffraction
(c) Photon momentum
(d) Photon diffraction

Answer

Answer: b

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34. The figure shows the variation of photocurrent with anode potential for a photosensitive surface for three different radiations. Let I_a, I_b and I_c be the intensities and v_a, v_b. and v_cbe the frequencies for the curves a, b and c respectively. Then the correct relation is

(a) v_a = v_b and I_a ≠ I_b
(b) v_a = v_c and I_a = I_c
(c) v_a = v_b and I_a = I_b
(d) v_b = v_c and I_b = I_c

Answer

Answer: a

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35. The photoelectric effect can be explained by
(a) Corpuscular theory of light
(b) Wave nature of light
(c) Bohr’s theory
(d) Quantum theory of light

Answer

Answer: d

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36. Work function of metal is
(a) the minimum energy required to free an electron from surface against coulomb forces.
(b) the minimum energy required to free an », nucleon.
(c) the minimum energy to ionise an atom.
(d) the minimum energy required to eject an electron orbit.

Answer

Answer: a

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37. The rest mass of a photon of wavelength X is

Answer

Answer: a

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38. Photoelectric effect is based on the law of conservation of
(a) energy
(b) mass
(c) linear momentum
(d) angular momentum

Answer

Answer: a

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39. Einstein’s photoelectric equation is:

Answer

Answer: a

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40. In photoelectric effect, the number of photoelectrons emitted is proportional to
(a) intensity of incident beam. –
(b) frequency of incident beam.
(c) velocity of incident beam.
(d) work function of photo cathode.

Answer

Answer: a

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41. Which of the following shows particle nature of light?
(a) Photoelectric effect
(b) Refraction
(c) Interference
(d) Polarisation

Answer

Answer: a

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42. Relativistic corrections become necessary when the expression for the kinetic energy 1/2 mv², becomes comparable with mc², where m is the mass of the particle. At what de Broglie wavelength, will relativistic corrections become important for an electron?
(a) λ = 10 nm
(b) λ = 10^-1 nm
(c) λ = 10^-4nm
(d) λ = 10^-3 nm

Answer

Answer: c

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43. Two particles A₁ and A₂ of masses m₁, m₂(m₁ > m₂) have the same de Broglie wavelength. Then,
(a) their momenta are the same.
(b) their energies are the same.
(c) energy of A₁ is greater than the energy of A₂
(d) energy of A₁ is equal to the energy of A₂

Answer

Answer: a

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44. Photons absorbed in a matter are converted to heat. A source emitting h photon/sec of frequency v is used to convert 1 kg or ice at 0°C to water at 0°C. Then, the time T taken for the conversion
(a) increases with increasing n, with v fixed
(b) decreases with n fixed, v increasing.
(c) does not remain constant with n and v changing such that nv = constant
(d) increases when the product nv increases.

Answer

Answer: b

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45. A particle moves in a closed orbit around the origin, due to a force which is directed towards the origin. The de Broglie wavelength of the particle varies cyclically between two values λ₁, λ₂ with λ₁ > λ₂. Which following statements are true?
(a) The particle could not be moving in a circular orbit with origin as centre.
(b) The particle could not be moving in an elliptic orbit with origin as its focus.
(c) When the de Broglie wavelength is λ₁ the particle is nearer the origin than when its value is λ₂.
(d) When the de Broglie wavelength λ₂, the particle is nearer the origin than when its value λ₁.

Answer

Answer: d

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46. Consider the following statements:
I. According to de Broglie hypothesis, particles have wave-like characteristics.
II. When an electron and a proton have the same de Broglie wavelength, they will have equal momentum.
Which of the above statements is/are correct?
(a) I only
(b) II only
(c) both I and II
(d) neither I nor II

Answer

Answer: c

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47. Maximum photoelectric current at particular intensity of incident radiation, which becomes independent of anode potential is known as __________ .

Answer/Explanation

Answer:
Explaination: saturation current

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48. Stopping potential is of intensity of incident radiation but proportional to __________ of the radiation.

Answer/Explanation

Answer:
Explaination: independent, frequency

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49. Kinetic energy and stopping potential are zero, when frequency of incident radiation is equal to __________ .

Answer/Explanation

Answer:
Explaination: threshold frequency

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50. According to Planck’s quantum theory of radiation, an electromagnetic wave travels in the form packets of energy called __________ .

Answer/Explanation

Answer:
Explaination: photon

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51. __________ experiment has varified and confirmed the wave nature of electrons.

Answer/Explanation

Answer:
Explaination: Davisson and Germer

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52. Photoelectric emission occurs only when the frequency of incident radiation is __________ than threshold frequency.

Answer/Explanation

Answer:
Explaination: greater

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53. Photoelectric emission is an __________ process.

Answer/Explanation

Answer:
Explaination: instantaneous

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54. De Broglie wavelength associated with an electron beam accelerated through a potential difference V is __________ proportional to √V.

Answer/Explanation

Answer:
Explaination: inversely

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55. __________ is the minimum amount of energy required to cause photoelectric emission.

Answer/Explanation

Answer:
Explaination: Wok function

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56. Wave associated with the material particle is known as __________ .

Answer/Explanation

Answer:
Explaination: matter wave

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57. Name the phenomenon which shows the quantum nature of electromagnetic radiation. [AI2017]

Answer/Explanation

Answer:
Explaination: Photoelectric effect.

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58. Define the term ‘threshold frequency’ in relation to photoelectric effect. [Delhi 2019, Foreign 2011]

Answer/Explanation

Answer:
Explaination:
Threshold frequency: For every metal surface, there is a minimum frequency of incident radiation, below which the photoelectric emission does not take place no matter what the intensity of incident radiation is and for how long the radiations are allowed to fall on the metal. This frequency is called threshold frequency.

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59. Show the variation of photocurrent with collector plate potential for different frequencies but same intensity of incident radiation. [AI 2017, Foreign 2011]

Answer/Explanation

Answer:
Explaination:
For same intensity but different frequencies v₁ > v₂ > v₃ of incident radiation.

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60. In photoelectric effect, why should the photoelectric current increases as the intensity of monochromatic radiation incident on a photosensitive surface is increased? Explain. [Foreign 2014]

Answer/Explanation

Answer:
Explaination:
An increase in intensity means increase in number of photons and thus, increase in photoelectric current.

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61. Show the variation of photocurrent with collector plate potential for different intensities but same frequency of incident radiation. [Delhi 2019, AI 2017, Foreign 2011]

Answer/Explanation

Answer:
Explaination:

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62. What is the rest mass of a photon?

Answer/Explanation

Answer:
Explaination: The rest mass of a photon is zero.

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63. The given graph shows the variation of photoelectric current (I) versus applied voltage (V) for two different photosensitive materials and for two different intensities of the incident radiation. Identify the pairs of curves that correspond to different materials but same intensity of incident radiation. [Delhi 2013]

Answer/Explanation

Answer:
Explaination: The materials with same intensity of incident light are 1 and 3; 2 and 4.

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64. The graph shows the variation of stopping potential with frequency of incident radiation for two photosensitive metals A and B. Which one of the two has higher value of work function? Justify your answer. [Chennai 2019, Dehradun 2019]

Answer/Explanation

Answer:
Explaination:
As threshold frequency of metal A is greater, its work function, Φ = hv₀, will also be greater than that of B.

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65. For a given photosensitive material and with a source of constant frequency of incident radiation, how does the photocurrent vary with the intensify of incident light? [Delhi 2014, AI 2011C]

Answer/Explanation

Answer:
Explaination:
The photoelectric current increases linearly with the intensity of light as shown in the figure.

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66. Ultraviolet radiations of different frequencies v₁ and v₂ are incident on two photosensitive materials having work functions W₁ and W₂ (W₁ > W₂) respectively. The kinetic energy of the emitted electrons is same in both the cases. Which one of the two radiations will be of higher frequency?

Answer/Explanation

Answer:
Explaination:
v₁ > v₂. As W₁ > W₂ and K.E. is same. From the relation,
hv = hv₀ + \(\frac{1}{2}\) mv²
and hv₀ = W= work function

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67. Two beams, one of red light and the other of blue light, of the same intensity are incident on a metallic surface to emit photoelectrons. Which one of the two beams emits electrons of greater kinetic energy? [HOTS]

Answer/Explanation

Answer:
Explaination:
The blue light emits the electrons of greater K.E., as v_b > v_r.

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68. Can non-metals show photoelectric effect? [HOTS]

Answer/Explanation

Answer:
Explaination: Yes, when they are exposed to electromagnetic radiations of higher frequency.

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69. A photosensitive surface emits photoelectrons when red light falls on it. Will the surface emit photoelectrons when blue light is incident on it? Give reason. [Foreign 2017]

Answer/Explanation

Answer:
Explaination:
Since condition for photoemission is \(\frac{h c}{\lambda} \geq \phi_{0}\) (work function) and λ_B < λ_R hence, surface will emit photoelectrons.

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70. What happens to the wavelength of a photon after it collides with an electron?

Answer/Explanation

Answer:
Explaination: The wavelength of a photon increases.

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71. State de Broglie hypothesis. [Delhi 2012]

Answer/Explanation

Answer:
Explaination:
“Particles of matter moving with a given velocity (momentum) can display wave-like properties”.
\(\lambda=\frac{h}{p}\)

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72. Write the expression for the de Broglie wavelength associated with a charged particle having charge q and mass m, when it is accelerated by a potential V. [AI2013]

Answer/Explanation

Answer:
Explaination:
De Broglie wavelength associated with a charged particle when accelerated by a potential V is given by
\(\lambda=\frac{h}{p}=\frac{h}{\sqrt{2 m q V}}\)
where m = mass of charge particle and q = charge on the particle

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73. A proton and an electron have same kinetic energy. Which one has smaller de Broglie wavelength and why? [AI 2012]

Answer/Explanation

Answer:
Explaination:

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74. Show on a graph the variation of the de Broglie wavelength (λ) associated with an electron with the square root of accelerating potential (V). [Delhi 2019, Similar Panchkula 2019, Foreign 2012]

Answer/Explanation

Answer:
Explaination:

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75. Write the relationship of de Broglie wavelength λ associated with a particle of mass m in terms of its kinetic energy E. [Delhi 2011C]

Answer/Explanation

Answer:
Explaination:
The required relation is given by \(\lambda=\frac{h}{\sqrt{2 m E}}\)

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76. Name an experiment which shows wave nature of electrons. Which phenomenon was observed in this experiment using an electron beam?

Answer/Explanation

Answer:
Explaination:
Experiment: Davisson and Germer
Phenomenon: Diffraction

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77. Two lines, A and B, in the plot given below show the variation of de Broglie wavelength, λ versus 1/√V, where V is the accelerating potential difference, for two particles carrying the same charge. Which one of two represents a particle of smaller mass?

Answer/Explanation

Answer:
Explaination:

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78. The de Broglie wavelength of a particle of kinetic energy K is λ. What would be the wavelength of the particle, if its kinetic energy were K/4 [HOTS]

Answer/Explanation

Answer:
Explaination:

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79. An electron and alpha particle have the same kinetic energy. How are the de Broglie wavelength associated with them related? [Similar Delhi 2019]

Answer/Explanation

Answer:
Explaination:

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80. Two metals A and B have work functions 2 eV and 5 eV respectively. Which metal has lower threshold wavelength?

Answer/Explanation

Answer:
Explaination:
Metal with work function 5 eV has lower threshold wavelength, i.e. metal B.

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81. Show graphically how the maximum kinetic energy of electrons emitted from a photosensitive surface varies with the frequency of incident radiations.

Answer/Explanation

Answer:
Explaination:

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82. What is the charge on metal in the photoelectric experiment?

Answer/Explanation

Answer:
Explaination: It will possess positive charge as it has lost electrons.

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83. What is the momentum of a photon of
(i) frequency v, and (ii) wavelength λ?

Answer/Explanation

Answer:
Explaination:
(i) Energy of photon
E = hv = mc²
∴ Momentum of a photon = mc = \(\frac{hv}{c}\)
(ii) The momentum of a photon of wavelength λ is p = \(\frac{h}{\lambda}\).
where h is the Planck’s constant.

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Free PDF Download of CBSE Physics Multiple Choice Questions for Class 12 with Answers Chapter 10 Wave Optics. Physics MCQs for Class 12 Chapter Wise with Answers PDF Download was Prepared Based on Latest Exam Pattern. Students can solve NCERT Class 12 Physics Wave Optics MCQs Pdf with Answers to know their preparation level.

Wave Optics Class 12 Physics MCQs Pdf

MCQ on Wave Optics Class 12 Question 1. Resolving power of telescope can be increased by increasing
(a) the wavelength
(b) the diameter of objective
(c) the diameter of eyepiece
(d) the focal length of eyepiece

Answer/Explanation

Answer: b
Explaination:
(b) The diameter of objective as R.P. of a telescope = \(\frac{D}{1.22 \lambda}\) R.P. is proportional 1.22 A to diameter of objective (D).

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Wave Optics MCQ Question 2. Polarisation of light proves
(a) corpuscular nature of light.
(b) quantum nature of light.
(c) transverse wave nature of light.
(d) longitudinal wave nature of light.

Answer/Explanation

Answer: c
Explaination: (c) transverse wave nature of light.

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Wave Optics Class 12 MCQ Question 3. The wavefront due to a source situated at infinity is
(a) spherical
(b) cylindrical
(c) planar
(d) circular

Answer/Explanation

Answer: c
Explaination: (c) The wavefront due to any source situated at infinity is planar.

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4. A laser beam is coherent because it contains
(р) waves of several wavelengths.
(b) incoherent waves of a single wavelength.
(c) coherent waves of several wavelengths
(d) coherent waves of a single wavelength.

Answer/Explanation

Answer: d
Explaination: (d) coherent waves of a single wavelength.

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MCQ on Wave Optics Pdf Question 5. If two sources have a randomly varying phase difference Φ(t), the resultant intensity will be given by

Answer/Explanation

Answer: c
Explaination:
(c) 2I₀, For two incoherent sources, the resultant intensity at every point is just twice of the two individual intensities.

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6. According to Huygens’ principle, light is a form of
(a) particle
(b) rays
(c) wave
(d) radiation

Answer/Explanation

Answer: c
Explaination:
(c) According to Huygens’ principle, light travels in the form of a longitudinal wave.

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Optics MCQ 14 Question 7. Two coherent monochromatic light beams of intensities I and 41 superimpose. The maximum and minimum possible intensities in the resulting beam are:
(a) 5I and I
(b) 5I and 3I
(c) 3I and I
(d) 9I and I

Answer/Explanation

Answer: d
Explaination:

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Wave Optics Questions with Answers Pdf Question 8. What is path difference for destructive interference?
(a) nλ
(b) n(λ +1)
(c) (2n + 1)\(\frac{\lambda}{2}\)
(d) (n +1)\(\frac{\lambda}{2}\)

Answer/Explanation

Answer: c
Explaination:
(c) (2n + 1)\(\frac{\lambda}{2}\) For destructive interference, the path difference is an odd multiple of λ/2.

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9. When exposed to sunlight, thin films of oil on water of ten exhibit brilliant colours due to the phenomenon of
(a) interference
(b) diffraction
(c) dispersion
(d) polarisation

Answer/Explanation

Answer: a
Explaination: (a) interference

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10. What happens, if the monochromatic light used in Young’s double slit experiment is replaced by white light?
(a) No fringes are observed.
(b) All bright fringes become while.
(c) All bright fringes have colour between violet and red.
(d) Only the central fringe is white and all other fringes are coloured.

Answer/Explanation

Answer: d
Explaination: (d) At central bright fringes of all wavelength overlap to produce white central fringe.

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11. When compact disk is illuminated by a source of white light, coloured lines are observed. This is due to
(a) dispersion
(b) diffraction
(c) interference
(d) refraction

Answer/Explanation

Answer: b
Explaination: (b) The small ripples on the compact disc split white light into the constituent colours.

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12. An unpolarised beam of intensity I0 is incident on a pair of nicols making angle of 60° with each other. The intensity of right emerging from the pair is

Answer/Explanation

Answer: d
Explaination:

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13. When unpolarised light beam is incident from air onto glass (n = 1.5) at the polarising angle.
(a) Reflected beam is polarised completely
(b) Reflected and refracted beams are partially polarised
(c) Refracted beam is plane polarised
(d) Whole beam of light is refracted

Answer/Explanation

Answer: b
Explaination: (b) The reflected fight is completely polarised.

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14. Resolving power of microscope depends upon
(a) wavelength of light used (directly proportional)
(b) wavelength of light used (inversely proportional)
(c) frequency of light used
(d) focal length of objective

Answer/Explanation

Answer: b
Explaination:

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15. The phenomenon of interference is based on
(a) conservation of momentum.
(b) conservation of energy.
(c) conservation of momentum and energy.
(d) quantum nature of light.

Answer/Explanation

Answer: b
Explaination: (b) conservation of energy

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16. A double slit interference experiment is carried out in air and the entire arrangement is dipped in water. The fringe width
(a) increases
(b) decreases
(c) remains unchanged.
(d) fringe pattern disappears.

Answer/Explanation

Answer: b
Explaination:

(b) Decreases

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17. In Young’s double slit experiment, if the monochromatic source of yellow light is replaced by red light, the fringe width
(a) increases
(b) decreases.
(c) remains unchanged.
(d) the fringes disappear

Answer/Explanation

Answer: a
Explaination: (a) Increases, as fringe width β ∝ λ(λ_yellow < λ_ed)

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18. In Young’s double-slit experiment, the intensity at the central maximum is I₀ if one of the slit is covered, then the intensity at the central maximum become:

Answer/Explanation

Answer: c
Explaination:

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19. The angle of incidence at which reflected light is totally polarised for reflection from air to glass (refractive index n) is

Answer/Explanation

Answer: d
Explaination:
(d) Polarising angle,
i = tan^-1 (n), (Brewster’s law)

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20. In Young’s double-slit experiment, the intensity is I at a point, where the path difference is \(\frac{\lambda}{6}\) (λ – wavelength of light used). If I₀ denotes the maximum intensity then \(\frac{I}{I_{0}}\) is equal to

Answer/Explanation

Answer: c
Explaination:
(c) As path difference,

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21. The idea of secondary wavelets for the. propagation of a wave was first given by
(a) Newton
(b) Huygens
(c) Maxwell
(d) Fresnel

Answer

Answer: b

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22. Light propagates rectilinearly, due to
(a) wave nature
(b) wavelengths
(c) velocity
(d) frequency

Answer

Answer: a

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23. Which of the following is correct for light diverging from a point source?
(a) The intensity decreases in proportion with the distance squared.
(b) The wavefront is parabolic.
(c) The intensity at the wavelength does not depend on the distance.
(d) None of these.

Answer

Answer: a

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24. The refractive index of glass is 1.5 for light waves of X = 6000 A in vacuum. Its wavelength in glass is
(a) 2000 Å
(b) 4000 Å
(c) 1000 Å
(d) 3000 Å

Answer

Answer: b

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25. The phenomena which is not explained by Huygen’s construction of wavefront
(a) reflection
(b) diffraction
(c) refraction
(d) origin of spectra

Answer

Answer: d

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26. A laser beam is used for locating distant objects because
(a) it is monochromatic
(b) it is not chromatic
(c) it is not observed
(d) it has small angular spread.

Answer

Answer: d

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27. Two slits in Young’s double slit experiment have widths in the ratio 81 :1. The ratio of the amplitudes of light waves is
(a) 3 :1
(b) 3 : 2
(c) 9 :1
(d) 6:1

Answer

Answer: c

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28. When interference of light takes place
(a) energy is created in the region of maximum intensity
(b) energy is destroyed in the region of maximum intensity
(c) conservation of energy holds good and energy is redistributed
(d) conservation of energy does not hold good

Answer

Answer: c

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29. In a double slit interference pattern, the first maxima for infrared light would be
(a) at the same place as the first maxima for green light
(b) closer to the centre than the first maxima for green light
(c) farther from the centre than the first maxima for green light
(d) infrared light does not produce an interference pattern

Answer

Answer: c

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30. To observe diffraction, the size of the obstacle
(a) should beX/2, where X is the wavelength.
(b) should be of the order of wavelength.
(c) has no relation to wavelength.
(d) should be much larger than the wavelength.

Answer

Answer: b

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31. The angular resolution of a 10 cm diameter telescope at a wavelength of 5000 A is of the order of
(a) 10⁶ rad
(b) 10^-2 rad
(c) 10^-4 rad
(d) 10^-6 rad

Answer

Answer: d

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32. The velocity of light in air is 3 * 108 ms-1 and that in water is 2.2 * 108 ms” . The polarising angle of incidence is
(a) 45°
(b) 50°
(c) 53.74°
(d) 63

Answer

Answer: c

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33. An optically active compound
(a) rotates the plane of polarised light
(b) changes the direction of polarised light
(c) does not allow plane polarised light to pass through
(d) none of these

Answer

Answer: a

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34. Consider a light beam incident from air to a glass slab at Brewster’s angle as shown in Figure.
A polaroid is placed in the path of the emergent ray at point P and rotated about an axis passing through the centre and perpendicular to the plane of the polaroid.

(a) For a particular orientation there shall be darkness as observed through the polaroid.
(b) The intensity of light as seen through the polaroid shall be independent of the rotation.
(c) The intensity of light as seen through the polaroid shall go through a minimum but not zero for two orientations of the polaroid.
(d) The intensity of light as seen through the polaroid shall go through a minimum for four orientations of the polaroid. [NCERT Exemplar]

Answer

Answer: c

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35. Consider sunlight incident on a slit of width 10⁴ A. The image seen through the slit shall
(a) be a fine sharp slit white in colour at the centre.
(b) a bright slit white at the centre diffusing to zero intensities at the edges.
(c) a bright slit white at the centre diffusing to regions of different colours.
(d) only be a diffused slit white in colour. [NCERT Exemplar]

Answer

Answer: a

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36. In a Young’s double slit experiment, the source is white light. One of the holes is covered by a red filter and another by a blue filter. In this case
(a) there shall be alternate interference patterns of red and blue.
(b) there shall be an interference pattern for red distinct from that for blue.
(c) there shall be no interference fringes.
(d) there shall be an interference pattern for red mixing with one for blue. [NCERT Exemplar]

Answer

Answer: c

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37. Figure shows a standard two slit arrangement with slits S₁ S₂. P₁ P₂ are the two minima points on either side of P (Figure). At P₂ on the screen, there is a hole and behind P₂ is a second 2- slit arrangement with slits S₃, S₄ and a second screen behind them. [NCERT Exemplar]

(a) There would be no interference pattern on the second screen but it would be lighted.
(b) The second screen would be totally dark.
(c) There would be a single bright point on the second screen.
(d) There would be a regular two slit pattern on the second screen.

Answer

Answer: d

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38. Consider the diffraction pattern for a small pinhole. As the size of the hole is increased
(a) the size decreases.
(b) the intensity decreases.
(c) the size increases.
(d) the intensity decreases. [NCERT Exemplar]

Answer

Answer: a

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39. For light diverging from a point source
(a) the wavefront is spherical.
(b) the intensity increases in proportion to the distance squared.
(c) the wavefront is parabolic.
(d) the intensity at the wavefront does not depend on the distance.

Answer

Answer: a

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40. A continuous locus of particles of medium vibrating in the same phase at any instant is known as _______ .

Answer/Explanation

Answer:
Explaination: wavefront

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41. Superposition of two waves in the same phase ‘ to produce maximum intensity is known as _______ interference.

Answer/Explanation

Answer:
Explaination: constructive

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42. Phenomenon of bending of light around comers of a small obstacle and spreading into region of geometrical shadow is called _______ of light.

Answer/Explanation

Answer:
Explaination: diffraction

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43. Resolving power of an optical instrument is _______ to limit resolution.

Answer/Explanation

Answer:
Explaination: reciprocal

---

44. Plane of polarisation is _______ to plane of vibration.

Answer/Explanation

Answer:
Explaination: perpendicular

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45. For a destructive interference, phase difference between wave is _______ .

Answer/Explanation

Answer:
Explaination: (2n – 1)π

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46. Path difference between two waves, having wavelength X and undergoing constructive interference is _______ .

Answer/Explanation

Answer:
Explaination: nλ

---

47. What is a phase difference between two points on the same wavefront?

Answer/Explanation

Answer:
Explaination: Zero.

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48. Sketch the shape of wavefront emerging from a point source of light and also mark the rays.

Answer/Explanation

Answer:
Explaination:

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49. What type of wavefront will emerge from a
(i) point source, and
(ii) distant light source?

Answer/Explanation

Answer:
Explaination:
(i) Point source — Spherical wavefront.
(ii) Distant light source—Plane wavefront.

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50. Draw the wavefront coming out of a convex lens when a point source of light is placed at its focus.

Answer/Explanation

Answer:
Explaination:

---

51. Draw the wavefront, if a point source is placed at point 2F of a convex lens.

Answer/Explanation

Answer:
Explaination:

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52. When monochromatic light travels from one medium to another its wavelength changes but frequency remains the same. Explain. [NCERT Example, Delhi 2011]

Answer/Explanation

Answer:
Explaination:
When a monochromatic light is incident on the surface separating two media, the atoms of the media interact with the light and may be viewed as oscillators, which take up the frequency of light causing forced oscillations.
Thus, the frequency remains same. But in medium, the speed changes, and accordingly the wavelength changes.

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53. When light travels from a rarer to a denser medium, the speed decreases. Does the reduction in speed imply a reduction in the energy carried by the light wave?

Answer/Explanation

Answer:
Explaination: No, as energy ∝ (amplitude)² and is independent of speed of wave.

---

54. What is meant by interference of light?

Answer/Explanation

Answer:
Explaination:
The phenomenon of non-uniform distribution of energy in a medium due to the superposition of two light waves from two coherent sources is called interference of light.

---

55. The interference fringe pattern according to the theory is hyperbola. What is the condition for seeing nearly straight fringes?

Answer/Explanation

Answer:
Explaination:
If distance between the plane of the two coherent sources and screen is very large compared to the fringe width; the fringes will be nearly straight lines.

---

56. Why are coherent sources required to create interference of light?

Answer/Explanation

Answer:
Explaination:
Without coherent sources, the intensity of the interference pattern will not be sustained.

---

57. State the reason, why two independent sources of light cannot be considered as coherent sources.

Answer/Explanation

Answer:
Explaination: They cannot keep a constant phase difference.

---

58. In the wave picture of light, intensity of light is determined by the square of the amplitude of the wave. What determines the intensity of light in the photon picture of light. [NCERT Example]

Answer/Explanation

Answer:
Explaination:
In photon picture, the intensity is determined as

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59. What is the effect on the interference fringes in a Young’s double slit experiment if the screen is moved away from the plane of the slits?

Answer/Explanation

Answer:
Explaination:
The angular separation of the fringes remains constant (=λ/d). The actual linear separation of the fringes increases in proportion to the distance of the screen from the plane of the two slits.

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60. What is the ratio of the fringe width for bright and dark fringes in Young’s double slit experiment? [HOTS]

Answer/Explanation

Answer:
Explaination: 1 : 1

---

61. How many interference fringes will be seenthe separation if the size of each slit is \(\left(\frac{1}{5}\right)^{th}\) the separation between the two slits?

Answer/Explanation

Answer:
Explaination:

---

62. How does the fringe width, in Young’s double slit experiment, change when the distance of separation between the slits and screen is doubled? [AI2012]

Answer/Explanation

Answer:
Explaination:
\(\beta=\frac{\lambda D}{d}\) As β ∝ D, when the distance between the slits and the screen is doubled.
The fringe width will also get doubled.

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63. When a monochromatic source is replaced by a source of white light in Young’s double-slit experiment, then which colour will appear closest to the central white fringe.

Answer/Explanation

Answer:
Explaination:
The fringe closest on either side of the central white fringe is red.
Explaination: For a point P for which S₂P – S₁P = \(\frac{\lambda_{b}}{2}\)
where λ_b represents wavelength for blud colour, the blue component will be absent and red colour fringe will appear. [λ_b < λ_R]

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64. What is the effect on the interference fringes in a Young’s double slit experiment, if the width of the source slit is increased? [NCERT Example]

Answer/Explanation

Answer:
Explaination:
As the source slit width increases, the fringe pattern gets less and less sharp. When the source slit is so wide that the condition s/S ≤ λ/d is not satisfied, the interference pattern disappears.

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65. One of the two slits in Young’s double slit experiment is so painted that it transmits half the intensity of the other. What is the effect on interference fringes? [HOTS]

Answer/Explanation

Answer:
Explaination: The contrast between the bright and dark fringes decreases.

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66. Why does the intensity of the secondary maximum become less as compared to the central maximum?

Answer/Explanation

Answer:
Explaination:
As the order increases only \(\frac{1}{n^{\mathrm{th}}}\) (where n is an odd number) of the slit will contribute in producing brightness at a point in the diffraction. So, the higher order maxima are not so bright as the central.

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67. How does the angular separation of interference fringes change, in Young’s experiment, if the distance between the slits is increased?

Answer/Explanation

Answer:
Explaination: Decreases, as θ = \(\frac{\lambda}{d}\)

---

68. What is the condition that only interference is observed in double slit experiment, diffraction is not?

Answer/Explanation

Answer:
Explaination:
When \(\frac{a}{d}\) << 1 then the diffraction pattern will become very flat and we observe only the interference pattern.

---

69. How are interference and diffraction consistent with the principle of conservation of energy?

Answer/Explanation

Answer:
Explaination:
In interference and diffraction, the light energy is redistributed. If it reduces in one region, producing a dark fringe, it increases in another region, producing a bright fringe. There is no gain or loss of energy, and the two phenomena are consistent with the principle of conservation of energy.

---

70. Why does the bluish colour predominate in a clear sky?

Answer/Explanation

Answer:
Explaination:
Our eyes are more sensitive to blue colour.

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71. An unpolarised light of intensity 1 is passed through a polaroid. What is the intensity of the light transmitted by the polaroid?

Answer/Explanation

Answer:
Explaination:
\(\frac{I}{2}\) as it will get polarised.

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72. If the angle between the axis of polariser and the analyser is 45°, write the ratio of the intensities of original light and the transmitted light after passing through the analyser.

Answer/Explanation

Answer:
Explaination:
As I = \(\frac{I_{0}}{2}\) cos² θ, where I₀ is the original intensity and 0 is the angle between the axis of the polariser and the analyser.

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73. Does the value of polarising angle depend on the colour of light?

Answer/Explanation

Answer:
Explaination: Yes, as μ = tan i_p and μ ∝ \(\frac{1}{\lambda^{2}}\)

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We hope the given Physics MCQs for Class 12 with Answers Chapter 10 Wave Optics will help you. If you have any query regarding CBSE Class 12 Physics Wave Optics MCQs Pdf, drop a comment below and we will get back to you at the earliest.

Free PDF Download of CBSE Physics Multiple Choice Questions for Class 12 with Answers Chapter 9 Ray Optics and Optical Instruments. Physics MCQs for Class 12 Chapter Wise with Answers PDF Download was Prepared Based on Latest Exam Pattern. Students can solve NCERT Class 12 Physics Ray Optics and Optical Instruments MCQs Pdf with Answers to know their preparation level.

Ray Optics and Optical Instruments Class 12 Physics MCQs Pdf

MCQ on ray optics class 12 Question 1. A converging lens is used to form an image on a screen. When the upper half of the lens is covered by an opaque screen.
(a) half the image will disappear.
(b) incomplete image will be formed.
(c) intensity of image will decrease but complete image is formed.
(d) intensity of image will increase but image is not distinct.

Answer/Explanation

Answer: c
Explaination:
(c) because focal length of lens does not change but amount of light passing through lens becomes half.

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2. In optical fibres, the refractive index of the core is
(a) greater than that of the cladding.
(b) equal to that of the cladding.
(c) smaller than that of the cladding.
(d) independent of that of cladding.

Answer/Explanation

Answer: a
Explaination:
(a) R.I. of core is greater than that of the cladding for total internal reflection to occur.

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Ray optics MCQ Questions pdf Question 3. An object is placed at a distance of 0.5 m in front of a plane mirror. The distance between object and image will be
(a) 0.25 m
(b) 0.5 m
(c) 1.0 m
(d) 2.0 m

Answer/Explanation

Answer: c
Explaination:
(c) Distance between object and image = 0.5 + 0.5 = 1.0 m

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4. Air bubble in water behaves as
(a) sometimes concave, sometimes convex lens
(b) concave lens
(c) convex lens
(d) always refracting surface

Answer/Explanation

Answer: b
Explaination:
(b) Air bubble in water behaves as a concave lens.

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MCQ on ray optics class 12 pdf 5. We combine two lenses, one is convex and other is concave having focal lengths /, and f2 and their combined focal length is F. Combination of the lenses will behave like concave lens, if
(a) f₁ > f₂
(b) f₁ = f₂
(c) f₁ < f₂.
(d) f₁ ≤ f₂

Answer/Explanation

Answer: a
Explaination:
(a) Focal length of the combination \(F=\frac{f_{1} f_{2}}{f_{1}+f_{2}}\), as f₂ is negative so denominator f₁ + f₂ must be positive or f₁ > f₂.

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Optics Multiple choice Questions and Answers pdf Question 6. The length of an astronomical telescope for normal vision (relaxed eye) will be

Answer/Explanation

Answer: d
Explaination:
(d) In normal vision, length of telescope L = f₀ + f_e

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Ray optics MCQ Question 7. The focal length of a biconvex lens of radii of each surface 50 cm and refractive index 1.5, is
(a) 40.4 cm
(b) 75 cm
(c) 50 cm
(d) 80 cm

Answer/Explanation

Answer: c
Explaination:

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8. A metal coin is at bottom of a beaker filled with a liquid of refractive index = 4/3 to height of 6 cm. To an observer looking from above the surface of liquid, coin will appear at a depth
(a) 1.5 cm
(b) 6.75 cm
(c) 4.5 cm
(d) 7.5 cm

Answer/Explanation

Answer: c
Explaination:

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9. Tom’ lenses of focal lengths ± 15 cm and ± 150 cm are available for making a telescope. To produce the largest magnification, the focal length of the eyepiece should be
(a) + 15 cm
(b) + 150 cm
(c) – 150 cm
(d) – 15 cm

Answer/Explanation

Answer:
Explaination:
(a) For telescope magnification,

to produce large magnification.

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10. If a convex lens of focal length 80 cm and a concave lens of focal length 50 cm are combined together, what will be their resulting power?
(a) + 6.5 D
(b) – 6.5 D
(c) + 7.5 D
(d) – 0.75 D

Answer/Explanation

Answer:
Explaination:
(d) Focal length of the combination

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Ray optics class 12 Questions and Answers pdf 11. A convex lens and a concave lens, each having the same focal length of 25 cm, are put in contact to form a combination of lenses. The power of the combination (in dioptres) is
(a) zero
(b) 25
(c) 50
(d) infinity

Answer/Explanation

Answer:
Explaination:

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12. The refractive index of the material of an equilateral prism is √3. What is the angle of minimum deviation?
(a) 45°
(b) 60°
(c) 37°
(d) 30°

Answer/Explanation

Answer:
Explaination:
(b) At minimum deviation position,

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13. In the formation of a rainbow, the light from the sun on water droplets undergoes
(a) dispersion only.
(b) only TIR.
(c) dispersion and TIR.
(d) scattering.

Answer/Explanation

Answer: b
Explaination:
(b) Rainbow is formed due to dispersion of sunlight by raindrops and total internal reflection inside the raindrop.

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14. In an experiment to find focal length of a concave mirror, a graph is drawn between the magnitude of u and v. The graph looks like

Answer/Explanation

Answer: c
Explaination: (c) u – v curve is a rectangular parabola.

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15. A convex lens of refractive index \(\frac{3}{2}\) has a power of 2.5 D in air. If it is placed in a liquid of refractive index 2 then the new power of the lens is
(a) – 1.25 D
(b) – 1.5 D
(c) 1.25 D
(d) 1.5 D

Answer/Explanation

Answer:
Explaination:

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16. A double convex lens of refractive index µ₁ is immersed in a liquid of refractive index µ₂. The lens will act as transparent plane sheet when
(a) µ₁ = µ₂
(b) µ₁ > µ₂
(c) µ₁ < µ₂
(d) µ₁ = \(\frac{1}{\mu_{2}}\)

Answer/Explanation

Answer:
Explaination:

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17. When a ray of light enters from one medium to another, then which of the following does not change?
(a) Frequency
(b) Wavelength
(c) Speed
(d) Amplitude

Answer/Explanation

Answer: a
Explaination:
(a) Only frequency of ray of light does not change when it propagates from one medium to another.

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18. A diver at a depth 12 m inside water (p = 4/3) sees the sky in a cone of semi-vertical angle

Answer/Explanation

Answer: c
Explaination:
(c) Required semi vertical angle = Critical angle i_c

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19. The astronomical telescope consists of objective and eyepiece. The focal length of the objective is
(a) equal to that of the eyepiece.
(b) shorter than that of eyepiece.
(c) greater than that of eyepiece.
(d) five times shorter than that of eyepiece.

Answer/Explanation

Answer: c
Explaination: (c) For producing large magnification focal length of objective is greater than that of the eyepiece.

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20. A rod of length 10 cm lies along the principal axis of a concave mirror of focal length 10 ’em in such a way that its end closer to the pole is 20 cm away from the mirror. The length of the image is
(a) 10 cm
(b) 15 cm
(c) 2.5 cm
(d) 5 cm

Answer

Answer: d

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21. For a total internal reflection, which of the following is correct?
(a) Light travels from rarer to denser medium.
(b) Light travels from denser to rarer medium.
(c) Light travels in air only.
(d) Light travels in water only.

Answer

Answer: b

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22. Critical angle of glass is θ₂ and that of water is θ₂. The critical angle for water and glass surface would be (μ_g = 3/2, μ_w = 4/3).
(a) less than θ₂
(b) between θ₁ and θ₂
(c) greater than θ₂
(d) less than θ₁

Answer

Answer: c

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23. Mirage is a phenomenon due to
(a) refraction of light
(b) reflection of light
(c) total internal reflection of light
(d) diffraction of light.

Answer

Answer: c

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24. A convex lens is dipped in a liquid whose refractive index is equal to the refractive index of the lens. Then its focal length will
(a) become zero
(b) become infinite
(c) become small, but non-zero
(d) remain unchanged

Answer

Answer: b

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25. Which of the following forms a virtual and erect image for all positions of the object?
(a) Concave lens
(b) Concave mirror
(d) Convex mirror
(d) Both (a) and (c)

Answer

Answer: d

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26. Two lenses of focal lengths 20 cm and – 40 cm are held in contact. The image of an object at infinity will be formed by the combination at
(a) 10 cm
(b) 20 cm
(c) 40 cm
(d) infinity

Answer

Answer: c

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27. Two beams of red and violet color are made to pass separately through a prism (angle of the prism is 60°). In the position of minimum deviation, the angle of refraction will be
(a) 30° for both the colors
(b) greater for the violet color
(c) greater for the red color
(d) equal but not 30° for both the colors

Answer

Answer: a

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28. Which of the following colours of white light deviated most when passes through a prism?
(a) Red light
(b) Violet light
(c) Yellow light
(d) Both (a) and (b)

Answer

Answer: b

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29. An under-water swimmer cannot see very clearly even in absolutely clear water because of
(a) absorption of light in water
(b) scattering of light in water
(c) reduction of speed of light in water
(d) change in the focal length of eye lens

Answer

Answer: d

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30. An astronomical refractive telescope has an objective of focal length 20 m and an eyepiece of focal length 2 cm. Then
(a) the magnification is 1000
(b) the length of the telescope tube is 20.02 m
(c) the image formed of inverted
(d) all of these

Answer

Answer: d

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31. An object is immersed in a fluid. In order that the object becomes invisible, it should
(a) behave as a perfect reflector.
(b) absorb all light falling on it.
(c) have refractive index one.
(d) have refractive index exactly matching with that of the surrounding fluid.

Answer

Answer: d

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32. A ray of light incident at an angle θ on a refracting face of a prism emerges from the other face normally. If the angle of the prism is 5° and the prism is made of a material of refractive index 1.5, the angle of incidence is [NCERT Exemplar]
(a) 7.5°
(b) 5°
(c) 15°
(d) 2.5°

Answer

Answer: a

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33. A short pulse of white light is incident from air to a glass slab at normal incidence. After travelling through the slab, the first colour to emerge is [NCERT Exemplar]
(a) blue
(b) green
(c) violet
(d) red

Answer

Answer: d

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34. An object approaches a convergent lens from the left of the lens with a uniform speed 5 m/s and stops at the focus. The image [NCERT Exemplar]
(a) moves away from the lens with an uniform speed 5 m/s.
(b) moves away from the lens with an uniform accleration.
(c) moves away from the lens with a non-uniform acceleration.
(d) moves towards the lens with a non-uniform acceleration.

Answer

Answer: c

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35. You are given four sources of light each one providing a light of a single colour – red, blue, green and yellow. Suppose the angle of refraction for a beam of yellow light corresponding to a particular angle of incidence at the interface of two media is 90°. Which of the following statements is correct if the source of yellow light is replaced with that of other lights without changing the angle of incidence? [NCERT Exemplar]
(a) The beam of red light would undergo total internal reflection.
(b) The beam of red light would bend towards normal while it gets refracted through the second medium.
(c) The beam of blue light would undergo total internal reflection.
(d) The beam of green light would bend away from the normal as it gets refracted through the second medium.

Answer

Answer: c

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36. The radius of curvature of the curved surface of a plano-convex lens is 20 cm. If the refractive index of the material of the lens be 1.5, it will [NCERT Exemplar]
(a) act as a convex lens only for the objects that lie on its curved side.
(b) act as a concave lens for the objects that lie on its curved side.
(c) act as a convex lens irrespective of the side on which the object lies.
(d) act as a concave lens irrespective of side on which the object lies.

Answer

Answer: c

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37. The direction of ray of light incident on a concave mirror is shown by PQ while directions in which the ray would travel after reflection is shown by four rays marked 1, 2, 3 and 4. Which of the four rays correctly shows the direction of reflected ray? [NCERT Exemplar]

(a) 1
(b) 2
(c) 3
(d) 4

Answer

Answer: b

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38. The optical density of turpentine is higher than that of water while its mass density is lower. Figure shows a layer of turpentine floating over water in a container. For which one of the four rays incident on turpentine in figure the path shown is correct? [NCERT Exemplar]

(a) 1
(b) 2
(c) 3
(d) 4

Answer

Answer: b

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39. A car is moving with at a constant speed of 60 km h^-1 on a straight road. Looking at the rear view mirror, the driver finds that the car following him is at a distance of 100 m and is approaching with a speed of 5 km h^-1. In order to keep track of the car in the rear, the driver begins to glance alternatively at the rear and side mirror of his car after every 2 s till the other car overtakes. If the two cars were maintaining their speeds, which of the following statement (s) is/are correct? [NCERT Exemplar]
(a) The speed of the car in the rear is 65 km h^-1.
(b) In the side mirror the car in the rear would appear to approach with a speed of 5 km h^-1 to the driver of the leading car.
(c) In the rear view mirror the speed of the approaching car would appear to decrease as the distance between the cars decreases.
(d) In the side mirror, the speed of the approaching car would appear to increase as the distance between the cars decreases.

Answer

Answer: d

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40. Consider an extended object immersed in water contained in a plane trough. When seen from close to the edge of the trough the object looks distorted. Which of the following is not correct.
(a) the apparent depth of the points close to the edge are nearer the surface of the water compared to the points away from the edge.
(b) the angle subtended by the image of the object at the eye is smaller than the actual angle subtended by the object in air.
(c) some of the points of the object far away from the edge may not be visible because of total internal reflection.
(d) water in a trough acts as a lens and magnifies the object.

Answer

Answer: d

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41. A magnifying glass is used, as the object to be viewed can be brought closer to the eye than the normal near point. This results in
(a) a larger angle to be subtended by the object at the eye and hence viewed in greater detail.
(b) the formation of a real inverted image.
(c) increase in the field of view.
(d) infinite magnification at the near point.

Answer

Answer: a

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42. An astronomical refractive telescope has an objective of focal length 20 m and an eyepiece of focal length 2 cm. Which one of the following is not correct?
(a) The length of the telescope tube is 20.02 m.
(b) The magnification is 1000.
(c) The image formed is inverted.
(d) An objective of a larger aperture will increase the brightness and reduce chromatic aberration of the image.

Answer

Answer: d

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43. Virtual image formed by convex mirror has magnification _________ .

Answer/Explanation

Answer:
Explaination: negative

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44. Optical denseness of a medium is measured in terms of _________ .

Answer/Explanation

Answer:
Explaination: refractive index

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45. Minimum angle of incidence in the denser medium for which angle of refraction becomes 90° is called _________ .

Answer/Explanation

Answer:
Explaination: critical angle

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46. Relation between critical angle and refractive index is _________ .

Answer/Explanation

Answer:
Explaination: \(\mu=\frac{1}{\sin i_{c}}\)

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47. Optical fibre works on the principle of

Answer/Explanation

Answer:
Explaination: Total internal reflection

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48. The splitting of white light into its constituent colours when it passes through a glass prism is called _________ .

Answer/Explanation

Answer:
Explaination: dispersion

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49. Blue colour of sky is due to phenomenon of _________ of sunlight.

Answer/Explanation

Answer:
Explaination: scattering

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50. A ray of monochromatic light passes from medium (1) to medium (2). If the angle of incidence in medium (1) is θ and the corresponding angle of refraction in medium (2) is θ/2, which of the two media is optically denser? Give reason. [Foreign 2013]

Answer/Explanation

Answer:
Explaination:

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51. For the same value of angle of incidence, the angles of refraction in three media A, B and C are 15°, 25° and 35° respectively. In which medium would the velocity of light be minimum? [AI2012]

Answer/Explanation

Answer:
Explaination:

Thus, the medium for which angle of refraction is of 15°, the speed of light is minimum.

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52. A concave lens of refractive index 1.5 is immersed in a medium of refractive index 1.65. What is the nature of the lens? [Delhi 2015]

Answer/Explanation

Answer:
Explaination: The nature of the lens is converging.

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53. A lens behaves as a converging lens in air and a diverging lens in water (μ = 4/3). What will be the condition on the value of refractive index (μ) of the material of the lens? [Delhi 2011C]

Answer/Explanation

Answer:
Explaination:
The refractive index p of the lens is less than the refractive index of water, i.e. \(\frac{4}{3}\) > μ_L > 1.

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54. An air bubble is formed inside water. Does it act as a converging lens or a diverging lens? [DoE]

Answer/Explanation

Answer:
Explaination: An air bubble behaves as a diverging lens inside the water.

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55. The image of an object formed by a lens on the screen is not in sharp focus. Suggest a method to get the clear focussing of the image on the screen without disturbing the position of the object, the lens or the screen.

Answer/Explanation

Answer:
Explaination:
The image of an object formed by a lens can be brought to a sharp focus on a unfixed screen by changing the focal length of the lens by any of the following methods:
(i) By placing another lens of suitable focal length in contact with the previous lens.
(ii) By immersing the given lens in a liquid of appropriate refractive index.

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56. Can absolute value of refractive index of a medium be less than unity?

Answer/Explanation

Answer:
Explaination:
As the speed of light is maximum in vacuum, therefore absolute value of refractive index cannot be less than unity as it is given by the relation n = \(\frac{c}{v}\).

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57. For which material the value of refractive index is (i) minimum and (ii) maximum?

Answer/Explanation

Answer:
Explaination:
(i) Refractive index is minimum for vacuum (μ = 1).
(ii) Refractive index is maximum for diamond.

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58. Can virtual image be photographed?

Answer/Explanation

Answer:
Explaination:
Yes, because the lens in the camera produces a real image of the virtual image being formed.

---

59. How does the angle of minimum deviation of a glass prism vary, if the incident violet light is replaced with red light? [Chennai 2019, AI 2017]

Answer/Explanation

Answer:
Explaination: It decreases.

---

60. An object is first seen in red light and then in violet light through a simple microscope. In which case is the magnifying power larger?

Answer/Explanation

Answer:
Explaination:
As we know m = 1 + \(\frac{D}{f}\)
∵ f_V < f_R
So, the magnifying power is larger when the object is seen in violet light.

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61. Name the phenomenon due to which one cannot see through the fog. [DoE]

Answer/Explanation

Answer:
Explaination: Due to scattering of light, one cannot see through the fog.

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62. How does the angle of minimum deviation of a glass prism of refractive index 1.5 change, if it is immersed in a liquid of refractive index 1.3?

Answer/Explanation

Answer:
Explaination: It will decrease.

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63. A convex lens is placed in contact with a plane mirror. A point object at a distance of 20 cm on the axis of this combination has its image coinciding with itself. What is the focal length of the lens? [Delhi 2014]

Answer/Explanation

Answer:
Explaination: The focal length of convex lens is 20 cm.

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64. If an object is moved from infinity to convex mirror, then in which direction will the image shift?

Answer/Explanation

Answer:
Explaination: The image will shift from focus to the convex mirror.

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65. A green light is incident from water to the air-water interface at the critical angle (θ). Which part of the spectrum will come out in the air medium?

Answer/Explanation

Answer:
Explaination: The spectrum of visible light whose frequency is less than that of green light will come out of the water into the air.

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66. How do the increasing (i) wavelength and (ii) intensity of light affect the speed of light in glass?

Answer/Explanation

Answer:
Explaination:
(i) ∵ v ∝ λ; ∴ speed of light increases on increasing the wavelength in glass.
(ii) There is no effect on speed of light on changing the intensity.

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67. Name the principle on which an optical fibre works.

Answer/Explanation

Answer:
Explaination: Total internal reflection.

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68. Why is there no dispersion in the light refracted through a rectangular glass slab?

Answer/Explanation

Answer:
Explaination:
A glass slab can be considered as two glass prisms placed together and the position of one prism is inverted w.r.t. another. Therefore, the various colours of white light dispersed by the first prism are again combined to form white light.

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69. The line AB in the ray diagram represents a lens. State whether the lens is convex or concave.

Answer/Explanation

Answer:
Explaination:
It is a diverging (concave lens) and the refracted rays are bending away from the principal axis.

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70. A ray of light incident on one of the faces of a glass prism of angle A has angle of incidence 2A. The refracted ray in the prism strikes the opposite face which is silvered, the reflected ray from it retracing its path. Trace the ray diagram and find the relation between the refractive index of the material of the prism and the angle of the prism.

Answer/Explanation

Answer:
Explaination:
Given: i = 2 A, r = 90° – (90° – A) = A

∴ n = 2 cos A

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71. Does the magnifying power of a microscope depend on the colour of the light used? Justify your answer. [Foreign 2017]

Answer/Explanation

Answer:
Explaination:
Magnifying power of a microscope,

Since the focal length of a convex lens depends on the refractive index, and refractive indices for different colours are different, so according to the lens maker’s formula

The magnifying power of a microscope depends on the colour of the light used.

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We hope the given Physics MCQs for Class 12 with Answers Chapter 9 Ray Optics and Optical Instruments will help you. If you have any query regarding CBSE Class 12 Physics Ray Optics and Optical Instruments MCQs Pdf, drop a comment below and we will get back to you at the earliest.

Free PDF Download of CBSE Maths Multiple Choice Questions for Class 12 with Answers Chapter 13 Probability. Maths MCQs for Class 12 Chapter Wise with Answers PDF Download was Prepared Based on Latest Exam Pattern. Students can solve NCERT Class 12 Maths Probability MCQs Pdf with Answers to know their preparation level.

Probability Class 12 Maths MCQs Pdf

1. Let A and B be two given events such that P(A) = 0.6, P(B) = 0.2 and P(A/B) = 0.5. Then P(A’/B’) is

Answer/Explanation

Answer: c
Explaination:

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2. Let A and B be two given independent events such that P(A) =p and P(B) = q and P(exactly one of A, B) = \(\frac{2}{3}\), then value of 3p + 3q – 6pq is
(a) 2
(b) -2
(c) 4
(d) -4

Answer/Explanation

Answer: a
Explaination:

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3. If P(A ∩ B) = 70% and P(B) = 85%, then P(A/B) is equal to

Answer/Explanation

Answer: a
Explaination:

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4. Two dice are thrown once. If it is known that the sum of the numbers on the dice was less than 6 the probability of getting a sum 3 is

Answer/Explanation

Answer: c
Explaination: (c), as favourable cases for sum less than 6 are 10 and favourable for a total of 3 is 2.

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5. Three balls are drawn from a bag containing 2 red and 5 black balls, if the random variable X represents the number of red balls drawn, then X can take values
(a) 0, 1, 2
(b) 0, 1, 2, 3
(c) 0
(d) 1, 2

Answer/Explanation

Answer: a
Explaination: (a), as there are 2 red balls, so maximum ’ red balls can be 2.

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6. The probability distribution of the discrete variable X is given as:

The value of k is
(a) 8
(b) 16
(c) 32
(d) 48

Answer/Explanation

Answer:
Explaination:

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7. Let A and B be two given mutually exclusive events. Then P(A/B) is _________ .

Answer/Explanation

Answer:
Explaination: 0, as P(A ∩ B) = 0 and P(A/B) = \(\frac{P(A \cap B)}{P(B)}\)

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8. If A and B are two independent events such that P(A) = \(\frac{1}{7}\) and P(B) = \(\frac{1}{6}\) then P(A’ ∩ B’) is _________ .

Answer/Explanation

Answer:
Explaination:

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9. Three persons A, B and C, fire a target in turn. Their probabilities of hitting the target are 0.2,0.3 and 0.5 respectively, the probability that target hit is _________ .

Answer/Explanation

Answer:
Explaination:
0.72, as /^target hit)
= P(at least one hits the target)
= 1 – P( none hits) =1 \(-P(\bar{A} \bar{B} \bar{C})\)

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10. If A and B are independent events, then P(A and B) = P(A) + P(B). State true or false.

Answer/Explanation

Answer:
Explaination: False, as P(A and B) = P(A) P(B).

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11. A speaks truth in 70% cases and B speaks truth in 85% cases. The probability that they speak the same fact is ______ .

Answer/Explanation

Answer:
Explaination:

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12. Given P(A) = 0.4, P(B) = 0.7 and P(B/A) = 0.6. Find P(A ∪ B).

Answer/Explanation

Answer:
Explaination: .
P(B/A) = \(\frac{P(A \cap B)}{P(A)}\)
⇒ 0.6 × 0.4 = P (A ∩ B)
⇒ P(A ∩ B) = 0.24
Now, P(A ∪ B) = P(A) + P(B) – P(A ∩ B)
= 0.4 + 0.7 – 0.24
= 0.86

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13. Given P(A) = \(\frac{1}{2}\) p(B) = \(\frac{1}{3}\) and P(A ∩ B) = \(\frac{1}{6}\). Are the events A and B independent?

Answer/Explanation

Answer:
Explaination:

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14. Prove that if E and F are independent events, then the events E and F are also independent. [Delhi 2017]

Answer/Explanation

Answer:
Explaination:
As E and F are independent events
∴ P(E ∩ F) = P(E)P(F) …(i)
Consider,
P(E)P(F) = P(E)[1 – P(F)]
= P(E) – P(E)P(F)
= P(E) – P(E ∩ F)
P(E)P(F’) = P(E ∩ F’)
⇒ E and F’ are independent events.

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15. A die, whose faces are marked 1, 2, 3 in red and 4,5,6 in green, is tossed. Let A be the event “number obtained is even” and B be the event “number obtained is red”. Find if A and B are independent events. [AI 2017]

Answer/Explanation

Answer:
Explaination:
A : number is even, i.e. 2, 4, 6; P(A) = \(\frac{3}{6}\)
= \(\frac{1}{2}\)
B : number is red, i.e. 1, 2, 3; P(B) = \(\frac{3}{6}\)
= \(\frac{1}{2}\)
A ∩ B : number is even and red, i.e. 2;
P(A ∩ B) = \(\frac{1}{6}\)
P(A) × P(B) = \(\frac{1}{2} \times \frac{1}{2}=\frac{1}{4}\)
As P(A ∩ B) ≠ P(A) . P(B)
Hence, not independent.

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16. A black and a red die are rolled together. Find the conditional probability of obtaining the sum 8, given that the red die resulted in a number less than 4. [CBSE 2018]

Answer/Explanation

Answer:
Explaination:
A : sum 8, i.e. (2, 6), (3, 5), (4, 4), (5, 3), (6, 2)
B : red die number less than 4.
B : (1, 1), (2, 1), (3, 1), (4, 1), (5, 1), (6, 1), (1, 2), (2, 2), (3, 2), (4, 2), (5, 2), (6, 2), (1, 3), (2, 3), (3, 3), (4, 3), (5, 3), (6, 3).
A ∩ B : (6, 2), (5, 3)
∴ Conditional probability of obtaining sum 8, given that red die resulted in number less than 4.

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17. 12 cards numbered 1 to 12 are placed in a box, mixed up thoroughly and then a card is drawn at random from the box. If it is known that the number on the drawn card is more than 3, find the probability that it is an even number.

Answer/Explanation

Answer:
Explaination:
Total cards are 12
A : number drawn is more than 3, i.e. 4, 5, 6, …, 12.
B : getting an even number, i.e. 2, 4, 6, 8, 10, 12.
A ∩ B : 4, 6, 8, 10, 12

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18. One card is drawn from a well shuffled pack of 52 cards. If E is the event “the card drawn is a king or a queen” and F is the event “the card drawn is an ace or a queen,” then find the probability of the conditional event E/F. [HOTS]

Answer/Explanation

Answer:
Explaination:

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19. Two cards are drawn from a well shuffled pack of 52 cards one after the other without replacement. Find the probability that one of them is a queen and the other is a king of opposite colour.

Answer/Explanation

Answer:
Explaination:

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20. A coin is tossed thrice and all eight outcomes are assumed equally likely. Let the event E be “the first throw results in head” and event F be “the last throw results in tail”. Find whether events E and F are independent.

Answer/Explanation

Answer:
Explaination:
Sample space
S = {HHH, HHT, HTH, THH, HTT, THT, TTH, TTT}
E: first throw results in head = {HHH,HHT,HTH,HTT}
F: Last throw result in tail = {HHT, HTT, THT, TTT}

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21. Two dice are thrown. Find the probability that the numbers appeared have a sum 8 if it is known that the second die always exhibits 4. [HOTS]

Answer/Explanation

Answer:
Explaination:
A: Sum of the numbers is 8, i.e. {(2,6), (3,5), (4,4), (5,3), (6,2)}
B: the second die always exhibits 4, i.e. {(1,4), (2,4), (3,4), (4,4), (5,4), (6,4)} A ∩ B= {(4, 4)}
Required probability,

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22. If P(A)=0.8,P(B)=0.5 andP(B/A)=0.4, find (i) P(A ∩ B) (ii) P(A/B) (iii) P(A ∪ B). [NCERT]

Answer/Explanation

Answer:
Explaination:

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23. The value of k, for which the following distribution is a probability distribution

Answer/Explanation

Answer:
Explaination:

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24. Find mean (µ) and variance (a2) for the following probability distribution:

Answer/Explanation

Answer:
Explaination:

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25. A random variable X has a probability distribution P(X) of the following form where k is some number:Determine (i) k (ii) P(X ≤ 2) (iii) P(X ≤ 2) (iv) P(X ≥ 2). [NCERT; Delhi 2019]

Answer/Explanation

Answer:
Explaination:

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We hope the given Maths MCQs for Class 12 with Answers Chapter 13 Probability will help you. If you have any query regarding CBSE Class 12 Maths Probability MCQs Pdf, drop a comment below and we will get back to you at the earliest.

Free PDF Download of CBSE Maths Multiple Choice Questions for Class 12 with Answers Chapter 12 Linear Programming. Maths MCQs for Class 12 Chapter Wise with Answers PDF Download was Prepared Based on Latest Exam Pattern. Students can solve NCERT Class 12 Maths Linear Programming MCQs Pdf with Answers to know their preparation level.

Linear Programming Class 12 Maths MCQs Pdf

1. Of all the points of the feasible region, for maximum or minimum of objective function, the point lies
(a) inside the feasible region
(b) at the boundary line of the feasible region
(c) vertex point of the boundary of the feasible region
(d) none of these

Answer

Answer: c

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2. A dealer wishes to purchase a number of fans and sewing machines. He has only ₹ 5,760 to invest and has space for at most 20 items. A fan costs him ₹ 360 and a sewing machine ₹ 240. He expects to sell a fan at a profit of ₹ 22 and a sewing machine at a profit of ₹ 18. Assinning that he can sell all the items that he buys, how should he invests his money to maximise the profit? The LPP for above question is
(a) x → fans, y → sewing machines
To maximise Z = 22x + 18y
subject to constraints
x ≥ 0, y ≥ 0, x + y ≤ 20
360x + 240y ≥ 5760
(b) x → fans, y → sewing machines
To maximise Z= 18x + 22y subject to constraints
x ≥ 0, y ≥ 0, x + y ≤ 20 360x + 240y ≥ 5760
(c) x → fans, y → sewing machines
To maximise Z = 22x + 18y
x ≥ 0, y ≥ 0, x + y ≥ 0
360x + 240y ≥ 5760
(d) x → fans, y → sewing machines
To maximise Z = 22x + 18j
x ≥ 0, y ≥ 0, x + y ≤ 20 360x + 240y ≤ 5760

Answer

Answer: d

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3. Feasible region is the set of points which satisfy
(a) the objective functions
(b) some of the given constraints
(c) all of the given constraints
(d) none of these

Answer

Answer: c

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4. An aeroplane can carry a maximum of 200 passangers. A profit of ₹ 400 is made on each first class ticket and a profit of ₹ 300 is made on each economy class ticket. An airline reserves at least 20 seats for first class. However, at least 4 times as many passengers prefer to travel by economy class than by first class. Find how many tickets of each type must be sold to maximise the profit? The LPP for the given situation is
(a) x → first class, y → economy class
To maximise Z = 400x + 300y
subject to constraints
x ≥ 0, y ≥ 0, x+y ≤ 200
x ≥ 20, y ≥ 80
(b) x → first class, y → economy class
To maximise Z 400x + 300y
subject to constraints
x ≥ 0, y ≥ 0, x+y ≥ 200
x ≥ 20, y ≥ 80
(c) x → first class, y → economy class
To maximise Z = 400x + 300y
subject to constraints
x ≥ 0, y ≥ 0, x ≥ 20
x + y ≤ 200
x ≥ 4y
(d) x → first class, y → economy class
To maximise Z = 400x + 300y
subject to constraints
x ≥ 20, y ≥ 0
x + y ≤ 200
y ≥ 4x

Answer

Answer: d

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5. A manufacturer makes two types of furniture, chairs and tables. Both the products are processed on three machines A₁ A₂ and A₃. Machine A₁ requires 3 hours for a chair and 3 hours for a table, machine A₂ requires 5 hours for a chair and 2 hours for a table and machine A₃ requires 2 hours for a chair and 6 hours for a table. Maximum time available on machine A₁, A₂ and A₃ is 36 hours, 50 hours and 60 hours respectively. Profits are ₹ 20 per chair and ₹ 30 per table. Formulate the above as a linear programming problem to maximise the profit. [HOTS]

Answer/Explanation

Answer:
Explaination:

Let x chairs and y tables are manufactured.
Then LPP is Maximise P = 20x + 30y
subject to the constraints, x ≥ 0, y ≥ 0, 3x + 3y ≤ 36, 5x + 2y ≤ 50, 2x + 6y ≤ 60.

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6. One kind of cake requires 200 g of flour and 25 g of fat and another kind of cake requires 100 g of flour and 50 g of fat, 5 kg of flour and 1 kg of fat is available, formulate the problem to find the maximum number of cakes which can be made, assuming that there is no shortage of the other ingredients used in making the cakes.

Answer/Explanation

Answer:
Explaination:
Let x cakes of kind I and y cakes of kind II are made.
Then LPP is
Maximise Z = x + y
subject to the constraints x ≥ 0, y ≥ 0
200x + 100y ≤ 5000
25x + 50y ≤ 1000

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7. A small firm manufactures necklaces and bracelets. The total number of necklaces and bracelets that it can handle per day is at mo£ 24. It takes one hour to make a bracelet and half an hour to make a necklace. The maximum number of hours available per day is 16. If the profit on a necklace is ₹ 100 and that on a bracelet is ₹ 300. Formulate an LPP for finding how many of each should be produced daily to maximise the profit? It is being given that at lea£ one of each muft be produced. [Delhi 2017]

Answer/Explanation

Answer:
Explaination:
Let x necklaces and y bracelets be produced.
Then LPP is
To maximise profit
Z =100x + 300y
subject to constraints
x ≥ 1, y ≥ 1
x + y ≤ 24; \(\frac{1}{2}\)x + y ≤ 16

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8. Two tailors, A and B, earn ₹ 300 and ₹ 400 per day respectively. A can stitch 6 shirts and 4 pairs of trousers while B can stitch 10 shirts and 4 pairs of trousers per day. To find how many days should each of them work and if it is desired to produce at least 60 shirts and 32 pairs of trousers at a minimum labour cost, formulate this as an LPP. [AI 2017]

Answer/Explanation

Answer:
Explaination:
Let A works for x days and B for y days
∴ LPP is to minimise Z = 300x + 400y
subject to the constraints 6x + 10y ≥ 60
4x + 4y ≥ 32
x ≥ 0, y ≥ 0

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We hope the given Maths MCQs for Class 12 with Answers Chapter 12 Linear Programming will help you. If you have any query regarding CBSE Class 12 Maths Linear Programming MCQs Pdf, drop a comment below and we will get back to you at the earliest.