1. A spaceship with rest mass m0 is traveling with an x-velocity V0x=+4/5 in the frame of the earth. it collides with a photon torpedo (an intense burst of light) moving in the -x direction relative to the earth. assume that the ship's shield totally absorbs the photon torpedo.
a) the oncoming torpedo is measured by terrified observers on the ship to have an energy of 0.75m0. what is the energy of the photon torpedo in the frame of earth?
b) use convervation of four-momentum to determine the final x-velocity (in the earth frame) and mass (in terms of m0) of the damaged ship after it absorbs the torpedo. use an energy-momentum diagram to solve this problem graphically.