http://nextbigfuture.com/2011/02/nasa-f ... -mach.html
Another counter-argument - either Paul March's own words or NBF making an argument based on March's argument, it's unclear based on the way the post is written - is made there:Imagine for the moment that two equations of MachEffect vehicles are true:
A = ΔV = KME × PELECTRIC / M
V = KME × PELECTRIC × T / M
EKINETIC = ½MV²
EKINETIC = ½M × ( KME × PELECTRIC × T / M )²
EKINETIC = ½K²P²T²/M
Which is to say the kinetic energy rises per the square of time ... since the K and E and M are constants. But, the energy put into the system is linear over time. Now - connect the dots - and you'll realize that when T = (2M)/(K²P) ... the amount of electric energy input to the Mach device equals the amount of kinetic energy of the craft itself. After that, the craft's energy exceeds the electrical energy input...
FACTOR VALUE UNITS NOTES
Mass 10,000.00 kg 10 ton craft
K 0.01 N/W low, but real conversion factor
P 9,800,000.00 W power needed for "1 G"
2M/K²P 20.41 sec sec, from dead stop, to kinetic energy exceeding electrical imput
A 9.80 m/s² Acceleration of craft
V 200.00 m/s velocity at cut-over where kinetic exceeds electrical
E 200,000,000 J Kinetic energy (== electrical input) at that point
It doesn't matter one whit whether the ME force (K) is really weak, or really strong - the equation works out to some time T where the kinetic energy of the moving vessel exceeds the energy actually put into it. After that point, it is a perpetual-motion machine (conceptually).
So we really have two things to discuss:The equations are not accurate, it is a simple restatement of the argument that was already covered in this thread 6 months ago.
The equations are incorrect because they are falsely constrained solutions to the ME equations Woodward derives. If you constrain mass to be constant, then yes, you get this result for these equations--but if you falsely constrain mass to be constant, than inertial fluctuations are obviously precluded as well.
So it's a variation of disproving the means(ME) by arbitrarily precluding the stated required conditions(variability of inertial mass) and working backwards to make it look scientific.
Dishonest line of argument. You can't disprove the statement "a+b=c" by starting from the assumption that "b" doesn't exist.
That's called "asking a different question.."
1. Does Goatguy's equation lead to the same result for any rocket so long as energy input and acceleration are constant? (Remember that according to one line of argument, even if you hook up a chemical rocket to a flywheel and make it accelerate constantly by feeding it fuel, if Goatguy is correct you should be able to accelerate it past T at which point it should start to generate power which you can use to manufacture more fuel which you feed back into it, also creating a perpetual motion machine. Or, just compare a Hall Thruster attached to a flywheel - if you feed it power to keep accelerating, does it reach a point where it can power itself?).
2. What do mass fluctuations do to the math?