The static energy of electrons: E0 = m (C0) 2 = (9.1*131) * (3 *108) 2 = 8.19 */kloc-.

Kinetic energy: ek = e-E0 = 5-0.512 = 4.488mev.

Momentum: p = (sqr ((e) 2-(E0) 2))/c = sqr ((5 *1.6 *10-13) 2-(0.512 *)

Speed: v = c * sqr ((e 2-e 02)/e 2) = 0.9947c.