A 75.0-kg halfback running north with a speed of 11.0 m/s is tackled by a 80.5-kg opponent running south at 7.5 m/s.The collision is perfectly inelastic.Compute the velocity of the two players just after the tackle.
A)9.2 m/s south
B)1.4 m/s south
C)1.4 m/s north
D)40 m/s north
E)9.2 m/s north

Question

Quizplus · Accepted Answer

In a perfectly inelastic collision, momentum is conserved. The total momentum before the collision is the sum of the individual momenta: (75 kg * 11 m/s) - (80.5 kg * 7.5 m/s). Solving for the final velocity of the combined mass (75 kg + 80.5 kg) gives 1.4 m/s north.

A 750-Kg Halfback Running North with a Speed of 11