On 26 Nov 2003 11:36:10 -0800, (Bill Never) wrote:

" Don't confuse watts with amps !!
The power rating of speakers is used as a sales point and usually bears
little resemblance to that actually developed, also of course in the average
unit the power developed will vary with the frequency.
You could expect a lower output with a mismatch of the 4ohm speakers.

Okay, This is where I get confused. The car has a 12 volt battery.

1) Does the amp produce 40 amps?

The amp produces a wattage at a given distortion level

2) Or is it powered by 40 watts?

The amp requires 12 volts. That's all.

3) Is the amp limited by the 12 volt battery?

Yes, The battery must supply 12 volts even at a high current draw.
If your battery can't produce this current then your amp will not
function up to specs.

I do not understand the difference between volts and watts/joules? Are
they not the same?

Where and how do volts become watts and vice versa?

Only worry about

volts/pressure
amps/volume of flow
wattage/ total power which is the volume at a given pressure.