Practice question · Select all that apply
Which expressions give the energy stored in a capacitor?
Hints
- Three are algebraically equivalent through Q = CV; one is dimensionally wrong.
- Substitute Q = CV into each and see which fails.
Show the answer
- A. Q squared over 2C
- C. One half C V squared
- D. One half Q V
Why
The first three are the same quantity written through . The fourth is not: substituting gives , which is not even an energy.
Practise Electrostatic Energy and Forces
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