On Jan 12, 2:05*pm, Cecil Moore wrote:
On Jan 12, 1:22 pm, Keith Dysart wrote:

P(t) = V(t) * I(t)
As corollary, the power at an instant of time is equal
to the voltage at that instant times the current at
that instant.

You obviously mean the *real* instantaneous voltage times the *real*
instantaneous current. You should say that to avoid confusion.

Seems you need to add 'Re' to that equation to remove the obvious
ambiguity. P(t) = Re[V(t)]*Re[I(t)]

From "Fields and Waves", by Ramo & Whinnery:

W(t) = {Re[Vm*e^j(wt+A1)]}{Re[Im*e^j(wt+A2)]}
--
73, Cecil, w5dxp.com

Good recovery.

But, of course, V(t) and I(t) are general functions
of time. In particular, the discusion was regarding
pulses.

Only when one constrains oneself to sinusoids and
chooses to use the complex exponential notation
is it necessary to use Re[].

But it was a good recovery.

...Keith