On 07/08/14 21:38, Keld Laursen wrote:
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)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.
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.There! You overunity seekers. Go back to lurking. We are not on perpetual motion yet. Unless I have overlooked something.
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. ;->