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BitWiz
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Problem: A nuclear generator produces energy used to accelerate a rocket. Given energy and mass, what is the acceleration a?
Nuclear generators produce energy in GeV or joules which have the dimensions L-2T-2M which has a force-over-distance (MaL) component which seems inappropriate or at least messy for acceleration. A better(?) unit, especially for delta-v, is force-over-time, ie impulse, with dimensions LT-2TM or LTM (momentum).
Impulse is then joules divided by (some) velocity. I can convert(?) by dividing joules by a "universal velocity" (the particle guys use c), or by forcing this (artificial) velocity to 1.0.(?)
In Case 1), a post on Wikipedia (here) in the "Momentum" section asserts that 1.0 GeV = 5.3 x 10-19 kgm/s which seems small by several orders of magnitude -- perhaps I don't understand what these units are really meant for ...
In Case 2), I'm forcing delta-v = aT = joules (where force is applied over exactly 1 meter) by using a unity velocity.
Despite the dimensional contortions, does the latter work? If so, are there hidden implications? For instance, the reaction mass used to propel the rocket could only be accelerated over 1.0 meters or this relationship falls apart, correct?
Are there any generalized equations for energy and power => impulse/momentum?
Thank you for your time.
Chris
Nuclear generators produce energy in GeV or joules which have the dimensions L-2T-2M which has a force-over-distance (MaL) component which seems inappropriate or at least messy for acceleration. A better(?) unit, especially for delta-v, is force-over-time, ie impulse, with dimensions LT-2TM or LTM (momentum).
Impulse is then joules divided by (some) velocity. I can convert(?) by dividing joules by a "universal velocity" (the particle guys use c), or by forcing this (artificial) velocity to 1.0.(?)
In Case 1), a post on Wikipedia (here) in the "Momentum" section asserts that 1.0 GeV = 5.3 x 10-19 kgm/s which seems small by several orders of magnitude -- perhaps I don't understand what these units are really meant for ...
In Case 2), I'm forcing delta-v = aT = joules (where force is applied over exactly 1 meter) by using a unity velocity.
Despite the dimensional contortions, does the latter work? If so, are there hidden implications? For instance, the reaction mass used to propel the rocket could only be accelerated over 1.0 meters or this relationship falls apart, correct?
Are there any generalized equations for energy and power => impulse/momentum?
Thank you for your time.
Chris