EASY
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A horizontal bridge is built across a river. A student standing on the bridge throws a small ball vertically upwards with a velocity 4 m s-1.
The ball strikes the water surface after 4 s. The height of bridge above water surface is
(Take g=10 m s-2):

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Important Questions on Measurements and Motion

HARD
In a car race, two cars start with velocities u1 and u2 and travel along a straight line with accelerations α and β respectively. If both reach the finish line at the same time then range of the race is
EASY
An object is thrown vertically with a velocity u. The velocity with which it strikes the ground on its return is
MEDIUM
A ball is projected vertically up from ground. Boy 'A' standing at the window of first floor of a nearby building observes that the time interval between the ball crossing him while going up and the ball crossing him while going down is 2 s. Another boy B standing on the second floor notices the time interval between the ball passing him twice, during up and down motion is 1 s. Calculate the difference between the vertical positions of boy B and boy A. (Assume g=10 m s-2)
HARD
Two particles A and B move from rest along a straight line with constant accelerations f and h, respectively. If A takes m seconds more than B and describes n units more than that of B acquiring the same speed, then
HARD
A stone thrown down with a seed u takes a time t1 to reach the ground, while another stone, thrown upwards from the same point with the same speed, takes time t2 . The maximum height the second stone reaches from the ground is
MEDIUM
A particle is projected vertically upwards. If it has to stay above the ground for 12 sec, then
HARD
A helicopter rises from rest on the ground vertically upwards with a constant acceleration g. A food packet is dropped from the helicopter when it is at a height h. The time taken by the packet to reach the ground is close to [g is the acceleration due to gravity]:
MEDIUM
A ball is dropped from the top of the building 100 m high. Simultaneously, another ball is thrown upwards from the bottom of the building with such a velocity that the balls collide exactly mid-way. What is the speed in m s-1 with which the second ball is thrown? (Take g=10 m s-2 )
EASY

A particle starts from origin O from rest and moves with a uniform acceleration along the positive  x-axis . Identify all figures that correctly represent the motion qualitatively.
( a= acceleration, v= velocity, x=  dispalcement, t= time)
A Question Image
B Question Image
(C) Question Image
(D) Question Image

MEDIUM
An object with mass 5 kg is acted upon by a force, F=(-3i^+4j^)N. If its initial velocity at t=0 is v=(6i^-12j^) ms-1, the time at which it will just have a velocity along y-axis is
EASY
A particle has initial velocity 2i^+3j^ and acceleration 0.3i^+0.2j^. The magnitude of velocity after 10 seconds will be
EASY
In a car race on straight road, car A takes a time t less than car B at the finish and passes finishing point with a speed v more than that of car B. Both the cars start from rest and travel with constant acceleration a1 and a2  respectively. Then v is equal to:
EASY
A ball is dropped from a height of 19.6 m. The distance covered by it in the last second is
HARD
From the top of a tower of height H, a body is thrown vertically upwards with a speed u. Time taken by the body to reach the ground is 3 times the time taken by it to reach the highest point in its path. Then, the speed u is
EASY
A body moving with uniform acceleration 6 m/s2 starts from rest. The distance covered by it in 4th  second will be
EASY
A boy pushes a box of mass 2 kg with a force F=20i^+10j^N on a frictionless surface. If the box was initially at rest, then _______ m is displacement along the x-axis after 10 s
HARD
An engine of a train, moving with uniform acceleration, passes the signal-post with velocity u and the last compartment with velocity v. The velocity with which middle point of the train passes the signal post is :
MEDIUM
A ship of mass 2×107kg initially at rest is pulled by a force of 5×105N, through a distance of 2m. Assuming that the resistance due to water is negligible, the speed of the ship is
HARD
A parachutist with total weight 75 kg drops vertically onto a sandy ground with a speed of 2 m s-1 and comes to a halt over a distance of 0.25 m. The average force from the ground on her is close to-
HARD
A piece of wood of mass 0.03 kg is dropped from the top of a 100 m height building. At the same time, a bullet of mass 0.02 kg is fired vertically upward, with a velocity 100 m s-1, from the ground. The bullet gets embedded in the wood. Then the maximum height to which the combined system reaches above the top of the building before falling below is: g=10 m s-2