CBSE 9th Physics Tutorials | Motion-Long Answer Type Question


Motion-Long Answer Type Question

Question 1. The following is the distance-time table of a moving car.

Time Distance Time Distance
10.05 am 0km 11.00 am 26 km
10.25 am 5 km 11.10am 28 km
10.40 am 12km 11.25 am 38 km
10.50 am 22 km 11.40 am 42 km

(i) Use a graph-paper and plot the distance traveled by the car versus time,

(ii) When was the car traveling with the greatest speed.:

(iii) What is the average speed of the car?

(iv) What is the speed between 11.25 am and 11.40am.

(v) During a part of the journey, the car was forced to slow down to 12 km/h, At what distance did this happen?

Answer (i)

The distance-time graph for the motion of the car is as shown in the figure given below

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Answer (ii)

The car is traveling with maximum speed between 10.40 am and 10.50 am as during this time the distance-time graph has maximum slope. Here

image

Question 2. What types of motion are represented by the following velocity-time graphs?

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Answer.

(a) The body has uniform velocity.

(b) The body has uniform acceleration and its initial velocity is zero.

(c) The body has some initial velocity and is under uniform retardation.

(d) The body has some initial velocity and uniform acceleration.

(e) The body has zero initial velocity and it has variable acceleration.

(f) The body is at rest from O to A, it has uniform acceleration from A to B, it has uniform velocity from B to C and from C to D, the body is under uniform retardation.

Question 3. A circular track has a circumference of 3140 m with AB as one of its diameter. A scooter moves from A to B along the circular path with a uniform speed of 10 m/s. Find distance covered by the scooter,displacement of the scooter, and time taken by the scooter in reaching from A to B.

Answer.

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