Question

1.Many people make the mistake of believing that when a larger defensive player collides with a wide receiver who is making a catch in the air, the larger defender must be exerting a bigger force on the smaller receiver, leading to a greater chance of injury. This, however, is not true. Explain why and which of Newton's 3 laws supports your answer.

Answer 1

Answer:

See explanation

Explanation:

Solution:-

- larger defensive player with mass (M) collides at velocity (vi) with a wide receiver with mass (m) and velocity (vf) who is making a catch in the air. The larger defensive player exerts a force on the wide receiver.

- The force exerted by the larger defensive player on the wide receiver must follow the "Newton's 3rd Law". The law states that for every action (Force) there must be an equal but opposite reaction.

- So according to the Newton's Law the interaction between larger defensive player and wide receiver has a pair of equal but opposite forces. Hence, both larger defensive player and wide receiver experience the same magnitude of force.

- However, the probability of injury is higher for the smaller receiver than larger defensive player because of the principle of conservation of momentum.

- Assuming.

                                      M > m

                                      vi > vf

- The principle of conservation of momentum is valid because there are no external forces acting on the system consisting of two bodies i.e (  larger defensive player and wide receiver ).

- So for momentum to be conserved:

                       Initial momentum = Final momentum

                       M*vi + m*vf = Final momentum

- We know that after collision the larger defensive player usually comes to a halt while the wide receiver springs into air. Assuming the velocity of larger player to be zero after collision and wide receiver to spring in air with velocity V. Then we have:

                       m*V = M*vi + m*vf

                       V = (M/m)(vi) + vf

- We see that the velocity of wide receiver is significantly higher than that increases the probability of injury for wide receiver.    

Answer 2

Answer: To every action there is an equal and opposite reaction. So as the defensive player collides with the receiver it feels an equal and opposite impact also.

Newton Third law of Motion

Explanation: