A bolt of mass 0.3 kg falls from the ceiling of an elevator moving down with an uniform speed of `7 m s^-1`. It hits the floor of the elevator (length of the elevator = 3 m) and does not rebound. What is the heat produced by the impact ? Would your answer be different if the elevator were stationary ?

A man of mass 70 kg stands on a weighing scale in a lift which is moving :- upwards with a uniform speed of 10 m s^-1 , what would be the reading on scale?

A bomb of mass 10 kg at rest explodes into two parts of 3 kg and 7 kg.If smaller part moves with a speed 14 m s^(-1) towards east ,find the velocity of the heavier part.

A bob of mass 0.1 kg hung from the ceiling of a room by a string 2 m long is set into oscillation. The speed of the bob at its mean position is 1 m s^-1 . What is the trajectory of the bob if the string is cut when the bob is:- at one of its extreme positions,

A bob of mass 0.1 kg hung from the ceiling of a room by a string 2 m long is set into oscillation. The speed of the bob at its mean position is 1 m s^-2 . What is the trajectory of the bob if the string is cut when the bob is:- at its mean position.

A trolley of mass 200 kg moves with a uniform speed of 36 km//h on a frictionless track. A child of mass 20 kg runs on the trolley from one end to the other (10 m away) with a speed of 4 m s^-1 relative to the trolley in a direction opposite to the its motion, and jumps out of the trolley. What is the final speed of the trolley ? How much has the trolley moved from the time the child begins to run ?

A body of mass 0.5 kg travels in a straight line with velocity v=a x(3/2) where a=5 m(1/2)s^-1 . What is the work done by the net force during its displacement from x = 0 to x = 2 m?

The total mass of an elevator with a 80 kg man in it is 1000 kg. This elevator moving upward with a speed of 8 ms^-1 is brought to rest over a distance of 16 m. Calculate the force exerted on man by the elevator floor.

A constant force acting on a body of mass 3.0 kg changes its speed from 2.0 m s^-1 to 3.5 m s^-1 in 25 s. The direction of the motion of the body remains unchanged. What is the magnitude and direction of the force ?

The total mass of an elevator with a 80 kg man in it is 1000 kg. This elevator moving upward with a speed of 8 ms^-1 is brought to rest over a distance of 16 m. Calculate the tension T in the cable supporting the elevator

An elevator of total mass (elevator+ passenger) 3600 kg in moving up with a constant speed of 2 ms^-1 . A frictional force of 1300 M opposes its motion. Determine the minimum power delivered by the motor to the elevator.