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**1. Homework Statement**

A cord connected at one end to a block which can slide on an inclined plane has its other end wrapped around a cylinder resting in a depression at the top of the plane as shown in the figure:

http://img35.imageshack.us/img35/6743/giancolich10p098.jpg [Broken]

Determine the speed of the block after it has traveled 1.40 m along the plane, starting from rest.

Assume the coefficient of friction between all surfaces is μ = 3.00×10^-2. [Hint: First determine the normal force on the cylinder, and make any reasonable assumptions needed.]

**2. Homework Equations**

Newton's second law in linear and angular form

**3. The Attempt at a Solution**

The forces on the block are fairly obvious: tension T, friction f, weight mg, and normal F.

However, I am not so sure about the forces on the cylinder. First there is T and Mg. I know there is a normal force N, but I wasn't sure of the direction so I drew it pointing to the upper left, an angle θ above the horizontal. I also was not sure about the frictional force. Is it perpendicular to N? If so, I got the following 4 equations in 4 unknowns:

[tex]

\]

\\

-Ncos\theta+Tcos27+\mu Nsin\theta=0 \\

\mu Ncos\theta+Nsin\theta-Tsin27-Mg=0 \\

T-f=.5Ma \\

-T-mg cos27+mg sin27=ma

\[

[/tex]

I can't seem to get the right answer from these though.

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