Question

14. A 5.00 kg ball hits a 75.0 kg man standing at rest on ice. The man catches the ball

How fast does the ball need to be moving in order to send the man off at a speed of
3.00 m/s?

Answer 1

V₁ = 48 m/s

Step-by-step explanation:

Using the Conservative Law of Momentum:

∑Qₓ = 0

Q₁ + Q₂ = 0

Q₁ = Q₂ (In absolute values)

Where:

Q₁: right before the impact

Q₂: right after the impact

So:

Q₁ = Q₂

m₁*V₁ + m₂*V₂ = m₁*V + m₂*V (Because both ball and man moves together)

5 * V₁ + 75 * 0 = (5 + 75)*3

5V₁ = 80 * 3

V₁ = 240/5

V₁ = 48 m/s