Question

PHYS101 21 . a) Write down expressions for the total energy, E, and the momentum, p, of a particle. Express your answers in terms of the rest mass, m, and velocity, u, of the particle. 4 marks) Using these expressions, show that E2-ap of the momentum. m2ct, where p Ipl is the magnitude (4 marks) b) A photon of frequency v is scattered trough 180° by an electron initially at rest in the laboratory. Show that the frequency of the scattered photon, , is given by hu where a is a constant whose value you should determine and m is the electron rest mass 9 marks c) Now consider a photon, whee energy is tuned to equal the rest mass energy of an electron. The photon is initially travelling in the +a direction when it collides head-on with an electron travelling in the - direction at speed V. If the scattered photon recoil in the -s direction, such that its energy is unchanged by the collision determine V. [8 marks)

Answer 1