A billiard ball traveling at 4.4 m/s has an elastic head-on collision with a billiard ball of equal mass that is initially at rest. The first ball is at rest after the collision.

Question

What is the speed of the second ball after the collision?

Answer 1

According to the law of conservation of momentum, the total momentum before collision is equal to the total momentum after collision.

Total momentum before: m₁ x 4.4 m/s + m₂ x 0

Total momentum after: m₂ x V₂ + m₁ x 0

m₁ x 4.4 m/s + m₂ x 0 = V₂ m₂ + m₁ x 0

Since m1 = m2, V2 = 4.4 m/s