It just is. You don't need a theoretical explanation, just go turn on a gas leaf blower and a battery operated one and see for yourself. The internal cumbustion engine is much louder than the actual blower mechanism.

Hah thanks, no matter how many times I re-read my posts I manage to miss something.

A lead blower would require a lot of battery power for sure.

Because its not running off of repeated explosions.

Have you compared your electric vacuum to your gas powered one?

Cars?