Power is the rate of doing work or using energy.
"Watt" means "joule per second".
If energy is used at the rate of 275 watts,
continuously for 20 seconds, then the
total amount of energy involved is
(275 joule/sec) x (20 sec) = 5,500 joules .
If the 275w is the power of something mechanical, like
an elevator, a crane, a pump, or a tractor, then the
5,500 joules of energy is the amount of mechanical work.
