# Yo-yo question (1 Viewer)

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#### vu10758

I have the question at http://viewmorepics.myspace.com/index.cfm?fuseaction=viewImage&friendID=128765607&imageID=1423959807

I have to determine what happens if each force is applied.

This is what I think.

If force one is applied, the yoyo will rotate clockwise, and friction will push it to the right.

If force three is applied, the yoyo will rotate counterclockwise and friction will push it to the left.

If force two is applied, the forces on the yoyo is zero and it will not move since friction and the force will balance each other out.

#### OlderDan

Homework Helper
I think you will need to quantify your answers to get these all correct. Assume friction is acting and is large enough to prevent slipping. If that assumption proves unreasonable in any case, then slipping should be included.

#### vu10758

The question specified that I am to assume that the yoyo roll smoothly without slipping.

#### OlderDan

Homework Helper
vu10758 said:
The question specified that I am to assume that the yoyo roll smoothly without slipping.
I wasn't sure if the handwritten part was in the problem, or an assumption. I suggest you put two different radii (inner and outer) in your diagram and assume the yo-yo is essentially a disk to find its moment of inertia. It's not absolutely necessary to do this, but I think it will help you analyze the situations.

Thank you.

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