In reply to Craig Haynie's message of Sun, 10 May 2015 23:19:42 -0400: Hi,
I'm suggesting that in theory no energy is required as long as there is no movement. IOW he creates a force, but as long as that force doesn't act over a distance, then it need do no work. E = F x d; F = m x a. E = m x a x d. You have calculated the mass times acceleration part of it. OTOH a rocket would most definitely expend energy just to hover, as do helicopters etc. but they also accelerate mass downward to produce the thrust (air in the case of helicopters). So I think it just depends on exactly how the thrust is generated, i.e. how the drive interacts with the space-time continuum. >His claim is 1 tonne of thrust per kilowatt. One tonne of thrust will >accelerate an object. An object under the acceleration of gravity will be >countered by the thrust, costing 48 kilowatts of power in the process. This >is not the same as suspending an object by a rope or something. Are you >suggesting that there is no theoretical limit as to how much power, applied >as thrust, is needed to suspend an object weighing a tonne? Or are you >suggesting that my math is wrong and that there is a lower number? If the >number is lower, then how do you arrive at it? > >Craig > > > > >On Sun, May 10, 2015 at 10:48 PM, <[email protected]> wrote: > >> In reply to Craig Haynie's message of Sun, 10 May 2015 18:07:28 -0400: >> Hi, >> [snip] >> >> It doesn't cost any energy at all to support a car. The ground does this >> just >> fine with no energy expenditure. E = F . d. If d = 0, then E = 0. >> I'm not sure how this applies to an EM drive (if at all), but perhaps it >> needs >> to be taken into consideration? >> >> >Hello! >> > >> >I was hoping the Vorts could help me with this. Roger Shawyer, at minute >> >2:56 in this video, claims that the next generation EM Drive could >> >generation 1 tonne of thrust per kilowatt of power. This means that a 1 >> >tonne car should be able to hover above the ground for the price of one >> >kilowatt. However, my calculation shows that to be about 48 times a >> >theoretical maximum. >> > >> >Here is the video where he makes the claim at 2:56. >> > >> >http://tinyurl.com/ko5v6h7 >> > >> >But here is my calculation for a theoretical maximum, calculated two >> >different ways: >> > >> > - >> > >> > A joule is a watt-second >> > - >> > >> > A watt is a joule / second >> > - >> > >> > The power required to hover an object is the same power required to >> > increase the speed of the object from rest, in a weightless >> environment, to >> > 9.8 m/s in one second. We know this because the pull of gravity is 9.8 >> > meters/second2. >> > - >> > >> > The kinetic energy in an object travelling at 9.8 m/s = 1/2 * m * v2. >> So >> > for a car of 1000 kg, the energy = 1000 / 2 * 9.82 = 48,020 joules = 48 >> > kilowatts to do this in one second. >> > - >> > >> > This power should be 1/2 the power to raise an object of the same mass, >> > to a height of 9.8 meters in one second, since it would require twice >> as >> > much energy to do this. >> > - >> > >> > The formula to determining how much energy it takes to raise something >> > to height = E = m * g (gravitational constant) * h = 1000 * 9.8 * 9.8 = >> > 96,040 watts-seconds = 96 kilowatts to do this in one second. So it >> agrees >> > with the previous result. >> > >> >So, I don't understand how any device could hover an object with the mass >> >of a tonne for less than a theoretical 48 kilowatts. Any thoughts on this >> >would be appreciated. >> > >> >Craig Haynie ( Manchester, NH) >> Regards, >> >> Robin van Spaandonk >> >> http://rvanspaa.freehostia.com/project.html >> >> Regards, Robin van Spaandonk http://rvanspaa.freehostia.com/project.html
