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## Homework Statement

http://img248.imageshack.us/img248/1639/cylinderjl0.jpg [Broken]

A uniform cylinder with a radius of R and mass M has been attached to two cords and the cords are wound around it and hung from the ceiling. The cylinder is released from rest and the cords unwind as the cylinder descends.

(a) draw a proper free body diagram for the cylinder;

(b) Apply Newton’s second law to the cylinder;

(c) apply Newton’s second law in rotational form to the cylinder;

(d) the two equations you have written so far

contain three unknowns; what is the relationship between the linear acceleration of the cylinder and its angular acceleration?

(e) Solve for the linear acceleration of the cylinder;

(f) What is the tension in the cords?

**The attempt at a solution**

A) The free body diagram should include the forces of tension pulling the cylinder up and the weight of the cylinder, right?

B) Essentially it would be Tension-weight of cylinder=angular acceleration, is that correct?

C)I know that Newton's second law in rotational form is:

Net external torque = moment of inertia x angular acceleration

So I would need to solve for moment of inertia:

I=mr^2 X Angular acceleration = net external torque.

D) So I have

Tension-weight of cylinder=angular acceleration

I=mr^2 X Angular acceleration = net external torque.

Linear Acceleration and Angular Acceleration are related by:

a. The Mass.

b. The Radius.

c. The Torque.

d. The Force.

In this problem, the mass, radius, and torque are unknown. The force working on the cylinder I believe is just gravity.

E and F) I am not sure how to do these.

I know this is a lengthy problem, but any help of guidance would be appreciately greatly! Even if ou don't know - I would settle for just a word of encouragement.

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