EEK! #6 – AC Power, RMS, and VA vs W

You probably do this all the time, but you don’t even know it.

I’m talking about AC power calculations with P = V x I.

Technically, it works. But when you think about it, it shouldn’t. AC has constantly changing voltage and current over time – unlike DC.

So how on earth does it work?

Well, the short version is: RMS, or root mean square!