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Q & A: capacitance units and energy

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Most recent answer: 06/05/2019
Q:
Hello, I'm trying to learn about electricity and specifically right now capacitors. Wikipedia entry on Farads says F=J/V^2, which I rearrange to Energy=Farads*(Volts squared). But many sources say Energy=1/2*Farads*(Volts squared). Obviously, these don't match and I'm hoping you can help me understand what I'm missing. Thank you
- Peter (age 57)
San Francisco, CA USA
A:

The actual physics equation is that energy = capacitance *voltage2/2. That equation can be used in maany different self-consistent systems of units. The Wikipedia entry is just describing how the Farad unit fits into the overall S.I. system of units. 

Mike W.


(published on 06/05/2019)

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