Calculating Angular Acceleration of a Rolling Cylinder on an Incline

[Truls]

A cylinder rolling down an incline.Moment of Interia is I
And the cylinders mass is m
Velocity is: v
And cylinder radius: r

Angel on the incline: yhttp://img122.imageshack.us/img122/8756/cylpz9.jpg

How do i calculate the cylinders angular acceleration?

 

[Truls]

ma=mg*$$\\siny$$

a=g*$$\\siny$$

angular acceleration:$$\alpha$$=a/r

Im i right?

 

[Truls]

Anyone?