[AR] Re: NASA test of quantum vacuum plasma thruster (was "Anyone heard of this?")
- From: Carlo Vaccari <airplaniac2002@xxxxxxxxx>
- To: arocket@xxxxxxxxxxxxx
- Date: Thu, 7 Aug 2014 10:32:08 -0400
A photon based propulsion system fails to generate free power because the
force is not invariant with relative speed.
On Aug 7, 2014 10:19 AM, "Jake Anderson" <jake@xxxxxxxxxxxxxxx> wrote:
> On 07/08/14 21:38, Keld Laursen wrote:
>
>> 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 that is not the case, as the RPM of the motor increases so will the
> voltage you need to supply and so will the power to maintain a torque
> output.
> (note the maintain a torque output part there, an ideal series wound motor
> with no load will reach infinity RPM)
>
>> There! You overunity seekers. Go back to lurking. We are not on perpetual
>> motion yet. Unless I have overlooked something.
>>
> The difference with the proposed thruster is the fixed power input results
> in a fixed force output regardless of the speed of the system, that is the
> bit where it breaks everything.
> And they have measurements that are perhaps less trustworthy than they
> initially seemed which supported their assertion.
> In all other cases the power demand to produce the torque is proportional
> to the speed of the system.
>
> It is an "unbalanced force", in every case F = MA if something pushes in
> one way it is balanced by something pushing in the other.
> If the thruster worked, sure it took power in, but it produces a force
> without pushing on something else and from there there are any number of
> ways of turning that into perpetual motion.
>
> I do still wonder where a photonic system fails and I'd really like to
> hear an explanation for why it would, though I fear the answer involves
> actual numbers not just abstract thought to work. ;->
>
>
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