EASY
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An object is released from point A, as shown in the figure below. Time taken by the object to move from B to C is 2 s. Find the height AC. Given that BC=80 m.

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Important Questions on Measurements and Motion

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
MEDIUM
A ball is dropped from the top of a 100 m high tower on a planet. In the last 12s before hitting the ground, it covers a distance of 19 m. Acceleration due to gravity (in m s-2 ) near the surface on that planet is______
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
MEDIUM
A tennis ball is released from a height h and after freely falling on a wooden floor it rebounds and reaches height h/2. The velocity versus height of the ball during its motion may be represented graphically by: (graphs are drawn schematically and on not to scale)
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-
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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]:
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
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
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
HARD
From a tower of height H, a particle is thrown vertically upwards with a speed u. The time taken by the particle, to hit the ground, is n times that taken by it to reach the highest point of its path.The relation between H, u and n is :
MEDIUM
Starting from the origin at time t=0, with initial velocity 5 j^ m s1, a particle moves in the x -y plane with a constant acceleration of 10i^+4j^ m s2. At time t, its coordinates are 20 my m. The values of t and y are, respectively:
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:
MEDIUM
A ball is thrown vertically downward with a velocity of 20 m s-1 from the top of a tower. It hits the ground after some time with a velocity of 80 m s-1. The height of the tower is: g=10 m s-2
EASY
An object is thrown vertically with a velocity u. The velocity with which it strikes the ground on its return is
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A person sitting in the ground floor of a building notices through the window, of height 1.5 m, a ball dropped from the roof of the building crosses the window in 0.1 s. What is the velocity of the ball when it is at the topmost point of the window? g=10 m s-2
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
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
MEDIUM
A bullet loses 1nth of its velocity passing through one plank. Considering uniform retardation, the number of such planks that are required to stop the bullet can be:
EASY
A body is thrown vertically upwards. Which one of the following graphs correctly represents the velocityv vs time t?
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