Question

Two objects with identical masses, m1 and m2, have an elastic collision. The initial velocity of m1 is +20 m/s and of m2 is +9.0 m/s. After the collision, the velocity of m1 is +9.0 m/s what will be the velocity of m2?

A) 20.0 m/s
B) 11.0 m/s
C) 13.0 m/s
D) 2.0 m/s

Answer 1

The velocity of m2 after the collision will be 20.0 m/s.

Step-by-step explanation:

In an elastic collision, both momentum and kinetic energy are conserved. We can use the principle of conservation of momentum to solve this problem.

Let's assume that the final velocity of m2 is v2. According to the conservation of momentum:

(m1 x initial velocity of m1) + (m2 x initial velocity of m2) = (m1 x final velocity of m1) + (m2 x final velocity of m2).

Plugging in the values:

(m1 x 20 m/s) + (m2 x 9.0 m/s) = (m1 x 9.0 m/s) + (m2 x v2)

Since both objects have identical masses, the equation becomes:

20 m/s + 9.0 m/s = 9.0 m/s + v2

Simplifying the equation:

29.0 m/s = 9.0 m/s + v2

Subtracting 9.0 m/s from both sides:

20.0 m/s = v2

Therefore, the velocity of m2 after the collision will be 20.0 m/s.