Hi, I'm kinda lost on these 2 problems.(adsbygoogle = window.adsbygoogle || []).push({});

A space probe is traveling in outer space with a momentum that has a magnitude of 7.15 x 107 kg·m/s. A retrorocket is fired to slow down the probe. It applies a force to the probe that has a magnitude of 1.81 x 106 N and a direction opposite to the probe's motion. It fires for a period of 9.56 s. Determine the momentum of the probe after the retrorocket ceases to fire.

On this first question I have no idea if I'm going to have to find the mass and than use the impulse momentum theorem? If so how would I go about finding the mass for it?

A student (m = 65 kg) falls freely from rest and strikes the ground. During the collision with the ground, he comes to rest in a time of 0.017 s. The average force exerted on him by the ground is +15000 N. From what height did the student fall? Assume that the only force acting on him during the collision is that due to the ground.

On this problem I think I'm suppose to apply the constant acceleartion equation to it? But I have no idea how to find the t in this problem. I don't think the 0.017s is the T that I'm suppose use?

Any help would be greatly appreciate it

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# Impulse Momentum Theorem and space probe

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