Physics-DPP-2-Kinematics

PHYSICS Topic: KINEMATICS Date: 1. A particle is projected vertically upwards and reaches the maximum height H in time T. The height of the particle at any time t will be: (a) g (t – T)2 (b) H – g (t – T)2 (c) 1 g (t – T)2 (d) H – 2 1 g (t – T)2 2 2. Two identical balls are shot upward one after another at an interval of 2s along the same vertical line with same initial velocity of 40 m/s. The height at which the balls collide is : (a) 50 m (b) 75 m (c) 100 m (d) 125 m 3. The figure shows the velocity (v) of a particle plotted against time (t). (a) The particle changes its direction of motion at some point (b) The acceleration of the particle remains constant (c) The displacement of the particle is zero (d) The initial and final speeds of the particle are the same 4. The figure shows velocity-time graph of a particle moving along a straight line. Identify the correct statement. (a) The particle starts from the origin (b) The particle crosses it initial position at t = 2s (c) The average speed of the particle in the time interval, 0  2s is zero (d) All of the above 5. A parachutist jumps out of an aircraft, falls freely for some time and then opens his parachute. Identify the graph which correctly represents his acceleration (a) versus time (t) graph : (a) (b) (c) (d) 6. A car is travelling on a road. The maximum velocity the car can attain is 24 m/s and the maximum deceleration is 4 m/s2. If car starts from rest and comes to rest after travelling 1032 m in the shortest time of 56 s, the maximum acceleration that the car can attain is : (a) 6 m/s2 (b) 1.2 m/s2 (c) 12 m/s2 (d) 3.6 m/s2 7. A car is moving with uniform acceleration along a straight line between two stops X and Y. Its speed at X and Y are 2 m/s and 14 m/s. Then : (a) its speed at mid point of XY is 10 m/s (b) its speed at a point A such that XA : AY = 1 : 3 is 5 m/s (c) the time to go from X to the mid point of XY is double of that to go from mid point to Y (d) the distance travelled in first half of the total time is half of the distance travelled in the second half of the time PHYSICS Topic: KINEMATICS Date: 8. A particle is thrown upwards from ground. It experiences a constant resistance force which can produce a retardation of 2 m/s2. The ratio of time of ascent to the time of descent is (g = 10 m/s2) (a) 1 : 1 (b) (c) 2 3 (d) 9. A balloon starts rising from the ground with an acceleration of 1.25 m/s2. After 8s, a stone is released from the balloon. The stone will (a) cover a distance of 40 m (b) have a displacement of 50 m (c) reach the ground in 4 s (d) begin to move down after being released 10. The displacement (x) of a particle depends on time (t) as x = t2 – t3. (a) The particle will return to its starting point after time /. (b) The particle will come to rest after time 2/3. (c) The initial velocity of the particle was zero but its initial acceleration was not zero. (d) No net force will act on the particle at t = /3. PHYSICS Topic: KINEMATICS Date: Answer Key 1. (d) 2. (b) 3. (a, b, c, d) 4. (b) 5. (b) 6. (b) 7. (a, b) 8. (b) 9. (c) 10. (a, b, c, d)

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