Hello there(adsbygoogle = window.adsbygoogle || []).push({});

I've been looking at this page

http://en.wikipedia.org/wiki/Relativistic_rocket

at the relativistic version of Tsiolkovsky rocket equation, but something puzzles me

With chemical rockets, the mass that is being converted into energy is so tiny that almost

all fuel mass can be considered to end up as propellant, but when we are talking about relativistic speeds, the energy requirements are so high that a major portion of fuel would end up being converted to energy.

What puzzles me is how to incorporate this into this equation.

For example, if 80% of the rocket mass was fuel, and there was, say a fusion process, and the product was propellant with kinetic energy equal to matter that was converted into energy how would you incorporate this into the equation? Because now, not all of the fuel mass is propellant, and yet there was indeed a loss in ships mass (which was converted into kinetic energy)

Any ideas?

Perhaps my assumptions about the equation are wrong.

I assumed that the mass ratios are just reaction mass vs. total mass, and have nothing to do with that portion of mass that is converted into energy

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# Relativistic rockets

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