Motion in A Str...

An elevator ascends with an upward acceleration of $$0.2\ m/s^{2}$$. At the instant when its upward speed is $$2\ m/s$$, a loose bolt $$5\ m$$ high from the floor drops from the ceiling of the elevator. The time taken by the bolt to strike the floor and the distance it has fallen are (Take $$g=9.8\ m/s^2$$)

A boy standing on an open car throws a ball vertically upwards with a velocity of $$9.8\ m/s$$, while moving horizontally with uniform acceleration of $$1\ m/s^{2}$$ starting from rest. The ball will fall behind the boy on the car at a distance of

A parachutist after bailing out falls for $$10$$ s without friction. When the parachute opens he descends with an acceleration of $$2\ m/s^{2}$$ against his direction and reached the ground with $$4$$ $$m/s$$. From what height he has dropped himself? $$(g=10\ m/s^{2})$$

A $$5\ kg$$ stone falls from a height of $$1000\ m$$ and penetrates $$2\ m$$ in a layer of sand. The time of penetration is

 A ball of mass $$100$$ gm is projected vertically upward from the ground with a velocity of $$50 ms^{-1}$$ . At the same time another identical ball is dropped from a height of $$100$$ m to fall freely along the same path as that followed by the first ball. After some time the two balls collide, stick together and finally fall to the ground. The time taken by the combined mass to fall to the ground is approximately $$(g=10 ms^{-2})$$

A ball is projected from the bottom of a tower and is found to go above the tower and is caught by the thrower at the bottom of the tower after a time interval $$t_{1}$$. An observer at the top of the tower finds the same ball go up above him and then come back to his level in a time interval $$t_{2}$$ .The height of the tower is

A particle starts from rest with uniform acceleration $$a$$. Its velocity after $$n$$ second is $$v$$. The displacement of the body in the last two second is

A ball is dropped from a high rise platform at $$t =0$$ starting from rest. After $$6$$ seconds another ball is thrown downwards from the same platform with a speed $$v$$. The two balls meet at $$t = 18\ s$$. What is the value of $$v$$ ?
(take $$g = 10\ m/s^{2}$$)

A stone is dropped into a well in which the water level is h below, the top of the well. If $$v$$ is velocity of sound, then time $$T$$ after which the splash is heard is equal to