One end of a light spring with force constant 300 N/m is attached to a vertical wall. A light string is tied to the other end of the horizontal spring. The string changes from horizontal to vertical as it passes over a solid pulley of diameter 6.00 cm. The pulley is free to turn on a fixed smooth axle. The vertical section of the string supports a 400 g object. The string does not slip at its contact with the pulley.
(a) Find the frequency of oscillation if the mass of the pulley is 450 g.
(b) Find the frequency of oscillation if the mass of the pulley is 750 g.