Physics-DPP-1-10.Kinematics

PHYSICS Topic: KINEMATICS Date: 1. An athlete completes half a round of a circular track of radius R, then the displacement and distance covered by the athlete are : (a) 2 R and πR (b) πR and 2R (c) R and 2πR (d) 2πR and R 2. A body moves 4 m towards east and then 3 m north. The displacement and distance covered by the body are : (a) 7 m, 6 m (b) 6m, 5m (c) 5m, 7m (d) 4m, 3m 3. A person travels along the straight road for half the distance with velocity v1 and the remaining half distance with velocity v2. Then average velocity is given by : (a) v v (b) v2 / v2 (c) (v + v )/ 2 (d) 2v v / (v + v ) 1 2 2 1 1 2 1 2 1 2 4. The velocity acquired by a body moving with uniform acceleration is 30 ms–1 in 2 seconds and 60 m s–1 in 4 seconds. The initial velocity is : (a) zero (b) 2 ms– 1 (c) 4 m s–2 (d) 10 ms–2 5. When the speed of a car is v, the minimum distance over which it can be stopped is s. If the speed becomes nu, what will be the minimum distance over which it can be stopped during same time? (a) s/n (b) ns (c) s/n2 (d) n2s 6. A stone is dropped from a certain height which can reach the ground in 5 sec. It is stopped after three seconds of its fall and then is again released. The total time taken by the stone to reach the ground will be (a) 6 s (b) 6.5 s (c) 7 s (d) 7.5 s 7. A person moves 30 m north and then 20 m towards east and finally 30 from the origin will be : m in south-west direction. The displacement of the person (a) 10 m along north (b) 10 m along south (c) 10 m along west (d) zero 8. A body falls freely from rest. It covers as much distance in the last second of its motion as covered in the first three seconds. The body has fallen for a time of : (a) 3 s (b) 5 s (c) 7s (d) 9 s 9. A particle moves along a straight line such that its displacement at any time t is given by s = (t 3 – 3t 2 + 2)m The displacement when the acceleration becomes zero is : (a) 0 m (b) 2m (c) 3 m (d) 2 s 10. A point moves in a straight line so that its displacement x m at time t sec is given by x2 = 1 + t2 . It acceleration in m/sec2 at a time t sec is : 1 t2 1 1 (a) 1/x3 (b) – t / x3 (c) x – x3 (d) x – x2 PHYSICS Topic: KINEMATICS Date: Answer Key 1. (a) 2. (c) 3. (d) 4. (a) 5. (b) 6. (c) 7. (c) 8. (b) 9. (a) 10. (a)

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