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 wagon that has a mass of 15 kg along a flat sidewalk with negligible friction by applying a force of magnitude 10 N at an angle of above the horizontal. The wagon is initially at rest.
How much work does the girl do on the wagon during the first 2.0 s that she pulls it along?
How much instantaneous power does she exert at s?