My attempts at getting an answer for this problem haven't been to good, this is the problem below:
A machine part has the shape of a solid uniform sphere of mass 255 grams and diameter 2.70 centimeters. It is spinning about a frictionless axle through its center, but at one point on its equator it is scraping against metal, resulting in a friction force of 0.0200 Newtons at that point.
Find its angular acceleration. Let the direction the sphere is spinning be the positive sense of rotation.
Based on what I have found in my physics book I've been using the following
A is alpha in this situation
T = IA I is moment of inertia
therefore T = Ffrictional * radius
so plugging it in I got .00027 for T
then for I using I = 2/5mr^2 and plugging it all in I got .00002 for I
so A = T/I and I got 13.5 for A which is incorrect
I don't see what I'm doing wrong please help. Thanks in advance.