Difference between revisions of "Power Efficiency"
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| − | + | P<sub>Useful</sub> = The useful power [[Energy Transfer|transferred]] to a device's intended purpose. | |
| − | + | P<sub>Total</sub> = The total power [[Energy Transfer|transferred]] to a [[system]]. | |
Revision as of 20:22, 2 February 2019
Key Stage 4
Meaning
Power efficiency is a ratio of useful power transferred to total power put into a system.
About Efficiency
- Power efficiency is a measure of how effectively energy is transferred from one energy store into an intended energy store.
- Efficiency may be written as a percentage or as a decimal.
- Efficiency as a percentage can never be greater than 100% and as a decimal can never be greater than 1 because you can never get more energy out than you put in due to Conservation of Energy.
Equation
Efficiency = (Useful Power Out)/(Total Power In)
\(Efficiency = \frac{P_{Useful}}{P_{Total}}\)
Where:
PUseful = The useful power transferred to a device's intended purpose.
PTotal = The total power transferred to a system.