- #1
kiwibird4
- 8
- 0
Since capacitors can store electrical energy in the form of a electrostatic field between its plates, one can derive that potential energy by looking at the work it takes to "push" the charges around to create the voltage.
Therefore Work =
integral from 0 to Q of V(q) dq =
integral from 0 to Q of (1/C)q dq =
Q^2/2C =
1/2 CV^2=
1/2 VQ which consequently equals the potential energy stored in the capacitor
so my question overall is::
Why it is not negative 1/2 VQ for PE since PE is the negative of work?
Everywhere I look there is never a -PE=W but they immediately equate the two being PE=W. I think I am missing something very simple here.
Therefore Work =
integral from 0 to Q of V(q) dq =
integral from 0 to Q of (1/C)q dq =
Q^2/2C =
1/2 CV^2=
1/2 VQ which consequently equals the potential energy stored in the capacitor
so my question overall is::
Why it is not negative 1/2 VQ for PE since PE is the negative of work?
Everywhere I look there is never a -PE=W but they immediately equate the two being PE=W. I think I am missing something very simple here.