[rescue] Workers of the World, Unite!

[James Lockwood]

On Mon, 22 Jul 2002, Joshua D Boyd wrote:

> Hmm, I'll have to double check what I did to my sister's stereo then.
> I have a bad feeling I might have put 4 ohm speakers on a 6 ohm amp.

Mismatching impedances is bad.  It is better to mismatch them (in this
case) in the direction that approximates an open circuit, though.  With a
higher impedance load the output stage of the amplifier will be
undersaturated, but it's better than oversaturation (which is more
nonlinear can lead to a failure in some designs).

> V=iR?  There isn't exactly any heat in that.  There is W=VA, which
> relates to heat...  Is that also part of ohm's law?

E=IR[1].  From this and P=EI we get P=E^2/R.

-James

1. Are people really learning "V", "W" and "A" now?