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Electricity and Magnetism

  1. Nov 29, 2011 #1
    My question is how do I find the voltage across a capacitor? I have an RLC circuit with a switch and battery. It only gives me the values for the battery, L, C, and R.

    My main question is, is there an equation or something to find the voltage across a capacitor?
  2. jcsd
  3. Nov 29, 2011 #2
    Is it connected in series? If so, according to Kirchhoff, V(t) = i(t)R + (1/C) int_0^t i(u)du + L di(t)/dt

    Solve that equation and you are done.
  4. Nov 30, 2011 #3
    If the battery is a constant voltage source (direct current), the voltage across the capacitor should be that voltage if you wait a sufficiently long time (typically a few seconds will do the trick, if the inductance is not too high).

    If it is an alternating current source, you will have to solve the equation posted by Termotanque.
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