[AR] Re: NASA test of quantum vacuum plasma thruster (was "Anyone heard of this?")
- From: "Keld Laursen" <kl@xxxxxxxxxxxxxxxx>
- To: <arocket@xxxxxxxxxxxxx>
- Date: Thu, 7 Aug 2014 13:38:46 +0200
I have seen it a couple of times now...
<snip />
<quote>
work = force * distance
power = work / time
Assuming the thruster takes a constant power input and produces a constant
output force regardless of its speed.
The thought experiment I propose is to put the thruster on an arm
connected to a generator so as the thruster thrusts the arm spins the
generator.
The power from the generator is going to be speed * force
(In the real world speed = volts, torque = amps)
As RPM of the motor goes up the power the generator makes will increase
for the same constant torque value.
At some point the power generated will exceed that required to run the
generator and presto you have a perpetual motion machine.
</quote>
<snip />
The problem with this is that it will work for anything. A series coupled DC
motor will run to infinity RPMs, and therefore you can attach a generator to it
and obtain overunity.
No! There are losses, so that the maximum RPM is dictated by the state where
losses use all the entered power.
So is It also with this illusive drive. As you speed up anything, including
your fancy spaceship in "empty" space, you will reach a point where losses to
the surroundings will eat up any extra supplied power?
There! You overunity seekers. Go back to lurking. We are not on perpetual
motion yet. Unless I have overlooked something.
Keld Laursen
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