The solution before revision #18602 of , by jzmicer. This is not the current version.
After it Changes Current version

Statement

14.5.23. [Insert the problem statement]

For problem $14.5.23$

Solution

A photon of mass collides with a stationary electron. Determine the mass of the photon and the electron after the collision, in which the photon changes its direction of motion by an angle .

Answer

[Insert a concise answer or boxed result]