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August 27, 2014

August 27, 2014

Posted by **J** on Monday, February 4, 2008 at 5:56pm.

I am totally confused I don't even know where to start. Help please!

- Physics -
**Damon**, Monday, February 4, 2008 at 6:16pmGee, I guess I better figure out how much energy is stored in a capacitor at voltage Vf and capacitance C

C = q/V

q = V C

dq/dt = i = C dV/dt

power = i V

power = C V dV/dt

so

power dt = C V dV

integral power dt = Energy = C integral V dV from V = 0 to V = Vf

but integral of x dx = (1/2)x^2 + constant

so

Energy at Vf = (1/2)C Vf^2

ok, now we can use that

Energy = (1/2)(450*10^-6)(295)^2

or

19.6 Joules

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