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FizzixIzFun

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**Momentum homework problem due this Tuesday**

## Homework Statement

Here's the question:

The surfaces are frictionless. The tracks are 60 degrees from horizontal. A 365 kg mass is released from rest on a track at a height 4.2 m above a horizontal surface at the foot of the slope. It collides elastically with a 480 kg mass initially at rest on the horizontal surface. The 480 kg mass slides up a similar track. The acceleration of gravity is 9.8 m/s^2. (A.) What is the speed of the 480 kg block immediately after the collision? Answer in units of m/s. (B.) To what maximum height above the horizontal surface will the 480 kg mass slide? Answer in units of m.

## Homework Equations

(I'm assuming by relevant equations, you mean the ones that I think are relevant. If you mean equations given in the problem, then disregard these two equations)

GPE= mgh

KE=(1/2)mv^2

## The Attempt at a Solution

(A.) I found the gravitational potential energy of the first block mgh=365 * 9.8 * 4.2 and then set that equal to (1/2)(365)(v^2) and solved for v. Is that the correct way to solve for the velocity of the 480 kg block since they collided elastically? (v=9.073 m/s)

(B.) I would assume that since the collision is elastic, the height the 480 kg mass would reach would be 4.2 (the height that the 365 kg mass started at). I feel like that is way to easy and that I must not be seeing something. (h=4.2m)

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