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Work=qV, but doesn't PE=1/2QV and PE=Work??
Electrical PE stored in Capacitor
- Thread starter Chocolatebear89
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I think qV is the potential energy of a constant electric field generated by a charge q.
1/2 QV is the potential energy of a capacitor with a charge of Q on either plate.
Also don't forget C = Q/V which you can combine with the previous equation to create a few other relationships.
Take it with a grain of salt though, this is an area where I'm pretty decent at solving problems but don't understand the theory very well. I'd love to hear a better explanation (the EK book skims through this whole branch of physics in like 5 pages).
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W=qV talks about how much work it takes to move a point charge, q, across a potential difference of V.
PE =1/2QV describes the PE of a capacitor with an overall charge Q and a potential difference of V.
These aren't universal equations. They work for specific situations. Also, the variable q and Q are different in this case. You have to know what the equation is describing, not just the equations themselves.
PE =1/2QV describes the PE of a capacitor with an overall charge Q and a potential difference of V.
These aren't universal equations. They work for specific situations. Also, the variable q and Q are different in this case. You have to know what the equation is describing, not just the equations themselves.
