Two masses m1 m and m2 m5 undergo an elastic collision in

Two masses m1 = m and m2 = m/5 undergo an elastic collision in 1 dimension, m1 is moving to the right with a speed of 10 m/s, m2 is moving to the left with a speed 25 m/s. After the collision m1 has a speed of 5 m/s to the left, what is the speed and direction of m2

Solution

Inital momentum of system

m*10 - m/5 *25 =5m

Final momentum -5m + m/5 *v

now 5m = -5m +m/5 *v

v= 50 m/s to the right