16.71 A uniform slender rod of length L = 900 mm and mass m 1 kg hangs freely from a hinge at A. If a force P of magnitude 3.5 N is ap- plied at B horizontally to the left (h= L), determine (a) the angular accel- eration of the rod, (b) the components of the reaction at A. L A-T B Fig. P16.71 P

Problems 7.80 through 7.82 The thin uniform bar AB of mass m and length L hangs from a wheel at A, which m freely on the horizontal bar DE. In the following problems, neglect the mass of the whd and assume that the wheel never separates from the horizontal bar. D. L. Figure P7.80-P7.82 Problem 7.80 If the bar is released from rest at the angle 0, determine, immediatey after release, the angular acceleration of the bar, the force on the bar at A, and the er eration of end A.

16.103 A 5-kg uniform square plate is supported by two identical 1.5-kg uniform slender rods AD and BE. It is held in the position shown by rope CF Determine, immediately after rope CF has been cut, (a) the ac celeration of the plate, (b) the force exerted on the plate at point B. 240 mm Fig. P16.103 A 240 mm 200 mm B

An automobile wheel test rig consists of a uniform disk A, of mass mà = 5000 kg and radius rà = 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 coincide at D, is mounted on a shaft (not shown) that holds D fixed while it allows the wheel to rotate about D. The wheel has diameter d = 0.62 m, mass mß = 21.5 kg, and mass moment of inertia about its mass center /D = 44 kg-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 on A. M B d A If M = 1200 N·m, use the angular impulse-momentum principle to determine how long it takes to reach conditions simulating a car speed of 100 km/h. The automobile wheel test rig takes s to reach conditions simulating a car speed of 100 km/h.

6.7 Three identical uniform, square plates, each of mass m, are attached to each other as shown in Fig. P6.7. Determine the value of 0 for which the radius of gyration of this assembly with respect to line L has a minimum value, and find this value. 90° Figure P6.7 Results 340°; 0.696b