Help with physics question which involves mechanics, rigid bodies.?

Question

A cylinder of radius R and mass M rolls down an incline as shown in the figure. (Figure is found at http://img223.imageshack.us/my.php?image=phyhelpcy0.png ) It starts from rest.

a) what is the cylinder's acceleration? Express its acceleration in terms of g (acceleration due to gravity) and theta.

b) what is the minimum coefficient of static friction, u, that is required for the cylinder to roll down the incline without slipping? express it in terms of theta.

Thanks a lot for helping! Your help is greatly appreciated.

Answer 1

♠ a=(2/3)*sin(theta);

still stewpid?