The office door of a professor is 0.99 m wide, 2.2 m high, 4.0 cm thick; consists of a mass of 26kg, and pivots on frictionless hinges. A "door closer" is joined to door and the top of the door frame. If the door is open and at rest, the door closer applies a torque of 5.8 N*m
Part A: Determine the moment of inertia of the door?
Part B: When you let go of the open door, determine its angular acceleration instantly afterward?