BENCHHMARK

CLASS -9

Chapter- MOTION

PHYSICS

WORKSHEET – 1

Multiple Choice Questions

1. A particle is moving in a circular path of radius r. The displacement after

half a circle would be:

(a) Zero

(b) π r

(c) 2 r

(d) 2π r

2. The numerical ratio of displacement to distance for a moving object is

(a) always less than 1

(b) always equal to 1

(c) always more than 1

(d) equal or less than 1

3. Which of the following figures (Fig. 8.3) represents uniform motion of a

moving object correctly?

4. In which of the following cases of motions, the distance moved and the

         magnitude of displacement are equal?

(a) If the car is moving on straight road

(b) If the car is moving in circular path

(c) The pendulum is moving to and fro

(d) The earth is revolving around the Sun

5. Unit of acceleration is

        A . m/s

       B) ms

      C) m/s²

    D) none of these

6) A body goes from A to B with a velocity of 20 m/s and comes back B to A with a velocity of 30 m/s. The average velocity of the body during the whole journey is

1. A) zero
2. B) 24 m/s
3. C) 25 m/s
4. D) none of these

    7. The rate of change of displacement with time is

      A) Speed

     B) acceleration

    C) Retardation

     D) velocity

     8. SI unit for the average velocity is

       A) m/s

       B) km/s

      C) cm/s

      D) none of these

  9. Unit for the rate of change of velocity is

       A) m/s

         B)m/s2

        C) N s

        D) N / s

10. A cylist moves from a certain point X and goes round a circle radius, r and reaches Y, exactly at the other side of the point X, as shown in the given figure.  (i) The displacement of the cylist would be: 

          A) πr

          B) 2πr

         C) 2r

         D) 2π/r

Solve the following 

1. An object cover a distance of 8 km in 2 minutes. Calculate the speed in:

             (a)  m/s                (b) Km/h.

2. Object A travelled a distance of 80 km in 4 hours and Object B travelled a distance of 100 km in 10 hours. Which object traveled faster?

3. Arrange the following speeds in increasing order-

              (a) Car moving with speed of 72 km/h

              (b)  A kite moving with speed of 10 m/s

              (c)  A train moving with speed of 1200 m/min

4. What is the displacement travelled by a car if it takes 30 minutes for a journey with velocity 20 m/s.

5. If a man walks at a speed of 2 km/h and walk a distance of 200 meters. How much time he will take to complete his walk?
6. A bus decreases its velocity from 80 km/h to 60 km/h in 5 s. find the acceleration of the body.

7. A train starting from a railway station and moving with uniform acceleration attains a speed 40 km/h in 10 minutes. Find its acceleration.

8. A motor boat starting from rest on a lake accelerates in straight line at a constant rate of 3.00 m/s² for 8.0 s. how far does the boat travel during this time?

9. A ball is gently dropped from a height of 20 m. if its velocity increases uniformly at a constant rate of 10 m/s^{2, .}With what velocity will it strike the ground? After what time will it strike the ground?

10. A bus starting from rest moves with a uniform acceleration of 0.1 m/s²for 2 minutes. Find

                      (a) The speed acquired.

                       (b) The distance traveled.