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A pitcher throws a ball to a catcher during the warm-up between innings. The pitcher takes $1.5 \; \text{s}$ to accelerate the ball to $35 \; \text{m/s}$ during the wind-up and release of the ball. The catcher stops the ball's motion in $0.05 \; \text{s}$ when the catcher catches it. Who exerts the greater impulse on the ball?

So I have an impulse problem that I am just not understanding and nothing I've searched for is helping me.

Now I am not looking for the answer here. I just need help to set it up considering that I've tried using the change in momentum to determine the impulse but to do that, I need the mass which is not given. I've tried doing the quantity of force and time but, again, that requires mass which I do not have. I am stuck on how to go about setting this up to solve it.

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You don't know the mass $m$ of the ball, but you know that $m$ is a constant, that is, $m$ is the same when the pitcher throws the ball as well as when the catcher chatches it. As the problem doesn't ask you to compute the absolute value of the impulses but just to say which one would be greater you should be able to answer it without knowing the value of the mass.

(It is like if I say you, in one hand I have an unknown mass and in the other I have two times that mass, which one feels heavier? You can answer it without knowing the value of the mass because it is just a relative question)

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Since the mass of the ball remains constant through time, and since $\Delta p = m \Delta v$, the mass doesn't matter and is not needed. In fact, only knowing that the impulse is the change in momentum can help you solve this problem quickly ;) (Further hint, work out the momentum using just "m" without any numbers, find out the change in momentum in each situation [before being thrown, after being thrown, after being caught] and see which impulse ends up being greater. )

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