Power is the rate of doing work. It is
the amount of work done per unit of time.
|
| Power = W/t |
The unit for power is Watts (W). 1 W = 1
J/s |
| W = work done |
| t = time |
|
An engine that will do the same amount of work as another in
half the time is twice as powerful. A person in good physical condition can deliver
work at a fairly continuous rate of roughly 75 W. Working at a steady pace, the
human body develops power in proportion to the amount of oxygen it consumes.
(Physics kicks in with biology!) |
Power Equivalencies |
| Quantity |
Equivalent |
| 1 joule per second |
1 W |
| 1 foot-pound per second |
1.356 W |
| 1 kilocalorie per hour |
1.16 W |
| 1 kilowatt-hour per day |
41.7 W |
| 1 kilocalorie per minute |
69.77 W |
| 1 horsepower |
745.7 W |
| 1 kilowatt |
1000 W |
| 1 gallon of gasoline per
hour |
39 kW |
| 1 gallon of oil per minute |
2.5 MW |
| 1 million barrels of oil per
day |
73 GW |
|
|
