A uniform rod of mass 4.2 kg and a length of 1.0 m is hinged to a wall at the left end and held in a horizontal position by a taut string. Then, the string is released. If the hinge is rusty and exerts a frictional torque of 5.0 Nm, then find:
a) the resulting angular acceleration of the rod?
b) the tangential acceleration of a point along the rod 0.85 m away from the hinge?
c) the tangential acceleration of a point along the rod 0.25 m away from the hinge?