[AR] Re: NASA test of quantum vacuum plasma thruster (was "Anyone heard of this?")
- From: Pierce Nichols <piercenichols@xxxxxxxxx>
- To: arocket@xxxxxxxxxxxxx
- Date: Thu, 7 Aug 2014 10:25:55 -0700
The theory paper written by the creator predicts a constant thrust/power
ratio. There's no velocity term in their equations.
-p
On Thu, Aug 7, 2014 at 9:41 AM, Nathan Mogk <nm8911@xxxxxxxxx> wrote:
> You aren't applying the same thought experiment here. No one on this list
> understands exactly how the device works, so in absence of any test data
> beyond static tests on a pendulum, there is no data for how the drive
> behaves, and the assumption is applied that it produces a constant
> thrust/power ratio under all circumstances. This is the assumption that
> causes the perpetual motion, which has nothing to do with the actual
> workings of the device. When asked to show how it isn't the same for
> another device, you did not apply the same assumption because you know the
> properties of the electric motor.
>
> This only shows the faultiness of that particular assumption in this
> thought experiment. It has nothing to do with the functioning of an actual
> device.
>
>
> On Thu, Aug 7, 2014 at 7:18 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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