Re: Joules - Vrms or Vp (fwd)

---------- Forwarded message ----------
Date: Tue, 28 Jul 1998 21:26:20 -0700
From: "Antonio Carlos M. de Queiroz" <acmq-at-compuland-dot-com.br>
To: Tesla List <tesla-at-pupman-dot-com>
Subject: Re: Joules - Vrms or Vp (fwd)

Barton B. Anderson wrote:

> Regarding the calculation for Joules..... J = 1/2 x C x
> V^2.
> Should V = Vp or should V = Vrms? Why? (if you know).

These are all instantaneous values. If you use V=Vpeak you
have the maximum energy in the capacitor. If you use V=Vrms
you get one half of the maximum energy, for a sinusoidal
signal. If you are using this formula to compute the maximum
energy per break in a primary circuit with the capacitor
charged by a transformer (without resonant charging), use
the peak value of the transformer output voltage.

Antonio Carlos M. de Queiroz