Suppose you have a device that extracts energy from ocean breakers in direct proportion to their intensity. If the device produces 10.0 kW of power on a day when the breakers are 1.20 m high, how much will it produce when they are 0.600 m high?
A man of mass 80.0 kg runs up a flight of stairs 20.0 m high in 10.0 s.
How much power is required for the man to rise this far in this time?
If the man’s body has an efficiency of for running up stairs, how much power was required for the run?
A girl pulls her 15-kg wagon along a flat sidewalk by applying a 10-N force at to the horizontal. Assume that friction is negligible and that the wagon starts from rest.
How much work does the girl do on the wagon in the first 2.0 s.
How much instantaneous power does she exert at s?
A dragster of mass 465.0 kg accelerates from rest to a final speed of 102.5 m/s over a distance of 415.0 m. The dragster accelerates against an average resistive force of N. What is its average power output if the acceleration takes 6.850 s?
A person does 6.00 MJ of useful work in s.
What is the person’s useful power output?
How long will it take this person to lift kg of bricks to a 1.50-m-height platform?