On Fri, 8 Aug 2008 08:10:49 -0400, "Eisboch" wrote:

True, but it's not particularly good for the motor. Ideally, it should
start up on "high" to give max torque using all the windings of the motor.
Then, it can be turned down. Not a big deal though ... most fans can
handle it. I forget the mechanical stuff, but it takes something like 3
times the amount of power to get something in motion than it does to
maintain that motion.

Actually the only force required to maintain motion is that required
to overcome friction or do work. Therefore the ratio is theoretically
infinite if the fan operates in a vacuum and has frictionless
bearings.