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Zokudu

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**[SOLVED] Rotational Momentum**

This is my first attempt at asking a question on here so please be gentle. I've been working on this problem for almost an hour and a half

## Homework Statement

In a circus performance, a large 3.0 kg hoop with a radius of 1.6 m rolls without slipping. If the hoop is given an angular speed of 5.6 rad/s while rolling on the horizontal and is allowed to roll up a ramp inclined at 18° with the horizontal, how far (measured along the incline) does the hoop roll?

**2. Relavent Equations**

1/2Iα^2=Rotational Momentum

1/2mv^2=kintetic Momentum

mgh=potential Momentum

V(tangent)=rω

I=1/2mr^2

**3. Attempt a Solution**

First i tried getting the rotational momentum and when i put the numbers in it comes out to about 60.221 kgm/s and then i set it equal to the potential momentum equation and got the height is 2.048m. However this answer came out as wrong.

So then i tried getting the tangential velocity and got 8.960 m/s and put that into the kentetic momentum equation and got 120.422 kgm/s (double what i got for rotational momentum) and set that to the potential energy equation and got 4.096m. Which is also wrong.

I think I am missing something to do with the ramp being 18 degrees above the horizontal but I am not sure where to add that into my math.

Please any help would be appreciated thank you.

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