View Single Post
Feb4-07, 05:07 PM
P: 1,270
Matter & Antimatter (2)

The "2" appears because there are 2 particles: matter & antimatter, and m is the mass of one of them.

So is the engine turned off at the moment it leaves the earth's surface and no further annihilation occurs? (i.e. the spaceship keeps going upward just by its inertia?)

And is the the process of mass lost (ldecreasing from 20000kg) finished BEFORE the spaceship is launched? (i.e. maintaining a constant mass as soon as it moves?)

Should I again assume ZERO kinetic energy of the matter/anti-matter before the collision? But if they are not moving, how can they collide?

The classical definition of total energy is kinetic + potential energy. I don't understand where the potential energy is accounted for in the total relativistic energy formula. (For example, if an object changes its height, its gravitational potential energy changes...but how come the term "potential energy" isn't appearing in the total relativistic energy equation?)

Thanks for your help!