Work and Energy...

What is the angle between displacement and the force applied, when the work done is maximum?

In the table given below energy transformations and different processes are listed. Match them.
 

The unit kgm²s^-2 is associated with

A crane pulls up a car of mass 650 kg to a vertical height of 4 m. What is the work done by the crane?

A force of 250 N on a block does a work of 2250 J. By how much length will the block be displaced?

Two bodies of equal mass move with uniform velocities of V and 2V respectively. Find the ratio of their kinetic energies.

A ball of mass 200 g falls from a height of 5 m. What is its kinetic energy when it just reaches the ground? (g = 9.8 m/sec²)

What is the work done by gravitational force when a body of mass 10 kg is dropped to the ground from a height of 10 meters?

(Take g = 9.8 ms^-2)

The K.E. of a running man is half to that of a boy half his mass. The man speeds up by 1 m/s and then has the same K.E. as the boy. What were the original speeds of the man and the boy?

A force `F` stops a body of mass `m` moving with a velocity `v` in a distance `s`, What is the force required to stop a body of double the mass moving with double the velocity in the same distance?