Question

football helmets are made with padding that helps reduce head injuries when a player collides with an object. which best explains how the padding reduces injuries? it extends the time of the collision. it reduces the time of the collision. it eliminates the reaction force of the object. it eliminates the action force of the object

Explanation:

According to the impulse - momentum theorem, impulse $J = F_{avg}\times\Delta t=\Delta p$. When the momentum change $\Delta p$ is constant (in a collision situation), increasing the time of collision $\Delta t$ reduces the average force $F_{avg}$. The padding in football helmets extends the time of the collision, thus reducing the average force exerted on the head and reducing injuries. The reaction and action forces cannot be eliminated due to Newton's third - law.

Answer:

It extends the time of the collision.