An observer O measures a particle of mass m moving in the x-direction to have speed Vz, energy E, and momentum p. Observer O', moving at speed u in the x-direction, measures v , E, and p' for the same object. (a) Use the Lorentz velocity transformation to derive the formulas for the relativistic total energy E' and relativistic momentum p' in terms of m, u, and v. (b) Reduce E2 - (p'c)? to its simplest form and interpret the result. [6] 19]