74) The problem asks for the reason that baseball catchers wear mitts rather than use their bare hands. It is crucial to identify that because we are talking about the ball slowing down from a high speed to zero, we must consider the momentum and impulse of the ball.
These are the two equations for impulse and we can use them to validate or refute each answer choice.
Choice A: Using the purple equation, we know that the ball's mass is a constant and whether the catcher has the mitt on or not, the ball will have to come to a stop from its initial velocity. This means that the impulse will remain the same whether the catcher is wearing the mitt or not. So, this choice cannot be correct.
Choice B: When the catcher uses the mitt, the time of the impact force applied is increased, and looking at the blue equation, to compensate, the magnitude of the force will decrease. Indeed, the magnitude of the force will decrease, but impulse doesn't have anything to do with the area of the glove. This means this choice is not right.
Choice C: An object's change in momentum is the same as its impulse. This answer explains the same situation as choice A, and for the same reason, it is still incorrect.
Choice D: This choice is very convincing. Just as we talked about during the choice B explanation, the time of impact will increase allowing the impact force to decrease. This is exactly what choice D explains so it could be our answer.
Choice E: This choice is invalid because if both the force and the time are reduced the impulse will not have the same magnitude as before, and just as we explained in choice A, the magnitude of the impulse must be constant because the object is slowing from its initial velocity to zero.
Answer: D
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