A shotput player throws a shot put of mass 3 kg, If it crosses the top of a wall of 2m height at a speedof 4 m/s, Compute the total mechanical energy of shot put when it croses the wall.

In a shotput event an athlete throws the shotput of mass 10 kg with an initial speed fo 1 ms^-1 at 45^@ from a height 1.5 m above ground. Assuming air resistance to be negligible and acceleration due to gravity to be 10 ms^-2 , the kinetic energy of the shotput when it jst reaches the ground wil be

A person trying to lose weight (dieter) lifts a 10 kg mass, one thousand times, to a height of 0.5 m each time. Assume that the potential energy lost each time she lowers the massis dissipated:- Fat supplies 3.8 xx 10^7J of energy per kilogram which is converted to mechanical energy with a 20% efficiency rate. How much fat will the dieter use up?

A ladder 5 m long is leaning against a wall. The bottom of the ladder is pulled along the ground, away from the wall, at the rate of 2cm/s. How fast is its height on the wall decreasing when the foot of the ladder is 4 m away from the wall ?

An object of mass 40 kg is raised to a height of 5 m above the ground. What is its potential energy ? If the object is allowed to fall, find its kinetic energy when it is half-way down. Take g = 10 ms ^-2 .

A player throws a ball upwards with an initial speed of 29.4 m s^-1 :- To what height does the ball rise and after how long does the ball return to the player’s hands ? (Take g = 9.8 m s^-2 and neglect air resistance).