If three locomotives are pulling a train, how much power does each locomotive need to apply on average during the first second to accelerate the train at from rest?

Jennifer throws a ball into the air. Her throw took . Determine the power of her throwing arm.

A man with mass 50kg is wearing a backpack of mass 5kg and running up a hill with a slope of 30 degrees at a constant velocity of . What is the man's power output?

During time period , a rocket ship deep in space of mass travels from to . During time period , the rocket fires. During time period , the rocket travels from to .

Time periods , , and took each.

Determine the average power during time period .

A car of mass goes from to in . Estimate the power of the engine.

If the transfer of of energy per second to a object results in the object experiencing a force of and a displacement of , how long will this process take? Assume there is no friction.

A car goes from to in . Estimate how long it would take the car to accelerate to , assuming the same engine power.

A locomotive accelerates a train from to in . Estimate the power of the locomotive during this time period.

Consider the following system:

Two spherical masses, A and B, are attached to the end of a rigid rod with length l. The rod is attached to a fixed point, p, which is at the midpoint between the masses and is at a height, h, above the ground. The rod spins around the fixed point in a vertical circle that is traced in grey. is the angle at which the rod makes with the horizontal at any given time ( in the figure).

This system is initially held so that the rod is in a horizontal position. At , the system is released and the rod is allowed to rotate. How much work is done by gravity by the time mass A reaches the lowest point of rotation?

Neglect air resistance. Assume the mass of the rod is zero.

You are on the ground floor of a parking garage building. You then run up the stairs to the roof, taking to reach a height of . You have a mass of . Determine your power in watts.