Motion and Time Class 7 Extra Questions and Answers Science Chapter 13

In this page, we are providing Motion and Time Class 7 Extra Questions and Answers Science Chapter 13 pdf download. NCERT Extra Questions for Class 7 Science Chapter 13 Motion and Time with Answers will help to score more marks in your CBSE Board Exams.

Class 7 Science Chapter 13 Extra Questions and Answers Motion and Time

Extra Questions for Class 7 Science Chapter 13 Motion and Time with Answers Solutions

Motion and Time Class 7 Extra Questions Very Short Answer Type

Question 1.
What is the use of speedometer?
Answer:
Speedometer is a device which is used in vehicles to measure the distance covered by the vehicle.

Question 2.
What is uniform motion?
Answer:
Uniform motion is that type of motion in which body travels equal distances in equal intervals of time.

Question 3.
What is speed?
Answer:
The speed of an object is defined as the distance travelled by the object in unit time.

Question 4.
State the formula of average speed of an object.
Answer:
Average speed = \(\frac{\text { Total distance travelled }}{\text { Total time taken }}\)

Question 5.
Which unit of speed will you use to express the speed of an aeroplane?
Answer:
km/s

Question 6.
Which kind of motion is described by a freely falling body?
Answer:
Linear motion.

Question 7.
What is the name of the device which measures the speed of a moving vehicle?
Answer:
Odometer

Question 8.
If A covers a certain distance in 30 minutes and B covers the same distance in 45 minutes, then who is travelling in higher speed?
Answer:
A is taking less time to cover the same distance, so it is travelling in higher speed.

Question 9.
What is the relation between distance and speed?
Answer:
Distance = Speed × Time

Question 10.
On what the time period of a simple pendulum depends?
Answer:
The time period of a simple pendulum depends upon its length.

Motion and Time Class 7 Extra Questions Short Answer Type

Question 1.
Describe how we calculate time period of a simple pendulum.
Answer:
The time period of a simple pendulum is the time taken by it to travel from A to B and back to A. When the bob moves from one extreme position A to the other extreme position B and comes back to A, it completes one oscillation.

Question 2.
What is motion? Describe briefly.
Answer:
An object that is moving with respect to time and another body is said to be in motion. Motion is measured as the distance covered by an object in a specific interval of time.

Question 3.
Differentiate between slow and fast objects.
Answer:
An object which takes longer time to cover a certain distance is called slow whereas another object which takes a shorter time to cover the same distance is called fast.

Question 4.
Anshika takes 15 minutes from her house to reach her school on bicycle the distance between her house and the school.
Answer:
Time taken = 15 min.
Speed = 2 m/s
Distance = Speed × time
= 15 × 60 × 2 = 1800 m
Thus, the distance between Anshika’s house and her school is 1800 m.

Question 5.
Draw the distance-time graph to show a car moving with a constant speed.
Answer:

Question 6.
What are the factors on which time period of a pendulum depends?
Answer:
Following are the factors on which time period of a pendulum depends:

• Length of the string of the pendulum.
• Acceleration due to gravity.

Question 7.
State one factor which is common in all the clocks.
Answer:
All the clocks show periodic motion.

Motion and Time Class 7 Extra Questions Long Answer Type

Question 1.
State the difference between uniform motion and non-uniform motion.
Answer:

Non-uniform motion	Uniform motion
(i) If the speed of an object moving along a straight line keeps changing, then this type of motion is called non-uniform motion.	(i) If the speed of an object moving along a straight line remains constant, then this type of motion is said to be uniform motion.
(ii) In this case, average speed is generally different from the actual speed.	(ii) In this case, the average speed is same as the actual speed.
(iii) The distance-time graph for non-uniform motion is a curved line.	(iii) The distance-time graph for uniform motion is a straight line.

Question 2.
Represent the following graphically:
(a) An object at rest
(b) An object moving with uniform speed
(c) An object moving with non-uniform speed
Answer:

Question 3.
The odometer of a car reads 24830 km at 1:25 PM, 24865 km at 2:05 PM and 25005 km at 3:15 PM. Calculate the speed of the car in km/h and m/s from 1:25 PM to 3:15 PM.
Answer:
D₁ = 24865 – 24830 = 35 km t₁ = 2:05 – 1:25 = 40 min
D₂ = 25005 – 24865 = 140 km t₂ = 3:15 – 2:05 = 50 min

Hence, speed of car is 116.7 km/h and 32.407 m/s.

Question 4.
Motion of A, B, C and D is plotted on a distance-time graph below. Study the graph and answer the following questions:

(a) Who is travelling fastest?
(b) Who is at rest?
(c) Who is moving in uniform motion?
(d) Who is accelerating with time?
(e) Who is moving slowest?
Answer:
(a) A
(b) C
(c) A
(d) B
(e) D

Question 5.
A scooter during its journey covers certain distances at different time intervals. Plot a graph by considering the following data and selecting a suitable scale. State whether the motion is uniform or nonuniform motion.

Distance (km)	15	30	45	60	75	90	105
Time (min.)	30	60	90	120	150	180	210

Answer:

The distance-time graph is a straight line so the motion of the scooter is uniform motion.

Motion and Time Class 7  Extra Questions HOTS

Question 1.
Complete the data of the table given below with the help of the distance-time graph.

Distance (m)	2	?	6	?	10	?	14
Time (s)	?	2	?	4	?	6	?

Answer:

Hence, the data is

Distance (m)	2	4	6	8	10	12	14
Time (s)	1	2	3	4	5	6	7

Question 2.
Starting from A, Somnath moves along a rectangular path ABCD as shown in Fig. 13.14. He takes 3 minutes to travel each side. Plot a distance-time graph and explain whether the motion is uniform or non-uniform. Find average speed of Somnath to move along the rectangular path.
Answer:



Since the distance covered per unit time for the entire distance is not the same, the motion is non-uniform motion.

Question 3.
The average age of students of class VII B is 12 years 4 months. Express the age in seconds.
Answer:
12 years 4 months = 12 × 365 + 4 × 30 = 4500 days
4500 days = 4500 × 24 × 60 × 60 = 388800000 s

Question 4.
Sitting in a classroom each student appears stationary to each other, whereas actually they are in motion. Explain.
Answer:
This is because of the earth in which we live is always in a state of motion around the sun and also along its axis.

Motion and Time Class 7 Extra Questions Value Based (VBQs)

Question 1.
Ritesh was riding a bicycle on the road, he said that the wheels of the bicycle are moving along a straight line. But his friend. Saket, who was also riding a bicycle said that the wheels of the bicycle are moving circular. They then decided rather than fighting among themselves it is better to ask their science teacher.
(a) Write some types of motion.
(b) What is rectilinear motion.
(c) What is rotatory or circular motion.
(d) Who among, Ritesh and Saket, is correct? Explain.
(e) What value of Ritesh and Saket is shown here?

Answer:
(a) Rectilinear motion, oscillatory motion, rotatory motion, random motion, etc.
(b) When the motion of a body is along a straight line, it is known as rectilinear motion.
(c) When a body moves about a fixed axis without changing its position, the body is said to have a rotatory motion.
(d) Ritesh and Saket, both are correct because wheels of the bicycle is showing both types of motion, i. e., rectilinear motion along the road as well as rotational or circular motion along a fixed axis.
(e) Ritesh and Saket both are intelligent and mature enough to not quarrel and inquisitive