Sahay Sir > Question Answers > Uncategorised (JEE Advanced Physics by BM Sharma + GMP Solutions) > wo bodies 1 and 2 of masses m and M are kept slightly separated . A third body 3 of mass m coming from left with velocity v makes a head- on elastic collision with m . Show that if m≥M there are exactly two collisions and find all final velocities and if m≤M there are three collisions and find all final velocities .

wo bodies 1 and 2 of masses m and M are kept slightly separated . A third body 3 of mass m coming from left with velocity v makes a head- on elastic collision with m . Show that if m≥M there are exactly two collisions and find all final velocities and if m≤M there are three collisions and find all final velocities .

An electron of mass m is involved in head-on collision with an atom of mass M initially at rest . As a result of the collision a certain amount of energy E is stored internally in the atom . What is the minimum initial velocity that the electron must have ?