A man holds a 10 kg box 2m above the ground.What is the work done?

What is work done?

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.

An artificial satellite is at a height of 36,500 km above earth's surface. What is the work done by earth’s gravitational force in keeping it in its orbit?

What is the S.I. unit of work done?

A ladder 10 m long reaches a window 8m above the ground. Find the distance of the foot of the ladder from base of the wall.

A stone is dropped from a rising balloon at a height of 75 m above the ground. It reaches the ground in 6 seconds. Calculate the velocity of the balloon just at the moment when the stone is dropped.

A rain drop of radius 2 mm falls from a height of 500 m above the ground. It falls with decreasing acceleration (due to viscous resistance of the air) until at half its original height, it attains its maximum (terminal) speed, and moves with uniform speed thereafter. What is the work done by the gravitational force on the drop in the first and second half of its journey? What is the work done by the resistive force in the entire journey if its speed on reaching the ground is 10 m s-^1 ?

A cricketer can throw a ball to a maximum,horizontal distance of 100 m. How much high above the ground can the cricketer throw the same ball?

An aircraft is flying at a height of 3400 m above the ground. If the angle subtended at a ground observation point by the aircraft positions 10.0 s apart is 30^@ what is the speed of the aircraft?

Water drops fall at regular intervals from a tap, which is 5 m above the ground. The third drop is leaving the tap at the instant the first drop touches the ground. How far above the ground is the second drop at that instant?