A solid sphere, starting from rest, rotates with constant angular acceleration α about a fixed axis passing through its center. Consider a particle within this sphere that lies at a perpendicular distance r from this axis. If, at some instant, the linear acceleration of this particle makes an angle of 50° with respect to the direction of its tangential acceleration, what is the total angle that the sphere has turned through up until that instant?
tangential acceleration = αr
centripetal acceleration = ω^2r
The Attempt at a Solution
Since the angular acceleration is constant, the tangential acceleration would also remain constant and I don't see how the angle could be changing.