The masses of the bar and disk are 14 kg and 9 kg, respectively. The system is released fr...

The masses of the bar and disk are 14 kg and 9 kg, respectively. The system is released from rest with the bar horizontal. Determine the bar’s angular acceleration at that instant if (a) the bar and disk are welded together at A and (b) the bar and disk are connected by a smooth pin at A.

Strategy: In part (b), draw individual free-body diagrams of the bar and disk.