Question

A ball, thrown right 6.00 m/s, hits a 1.25 kg panel at rest, then bounces back at 1.90 m/s. The panel moves right at 1.09 m/s. Find the ball's mass.

Answer 1

Answer:

0.172 kg

Explanation:

Using the law of conservation of momentum:

m1u1 + m2u2 = m1v1 + m2v2

where 1 is subscript for ball and 2 is subscript for panel

u1 = 6, u2 = 0

v1 = -1.9, v2 = 1.09

6m1 + 0 = -1.9m1 + (1.25 x 1.09)

7.9m1 = 1.3625

m1 = 0.172 kg