An automobile wheel test rig consists of a uniform disk A, of mass mA = 5000kg and radius...

An automobile wheel test rig consists of a uniform disk A, of mass mA = 5000kg and radius rA = 1.5 m, that can rotate freely about its fixed center C and over which the wheel of an automobile is made to roll. A Wheel B, whose center and center of mass at D, is mounted on a shaft (not shown) that holds D fixed while allowing the wheel to rotate about D. The wheel has diameter d = 0.62m, mass mB = 21.5kg, and mass moment of inertia about its mass center ID = 44kg·m2. Both A and B are initially at rest when B is subject to a constant torque M that causes B to roll without slip over A.

Use the angular impulse-momentum principle and determine M if it takes 15 seconds to achieve conditions simulating a car speed of 60 km/h.

Figure P8.95