R14-6. The 50-lb load is hoisted by the pulley system and motor M. If the motor exerts a constant force of 30 lb on the cable, determine the power that must be supplied to the motor if the load has been hoisted s = 10 ft starting from rest. The motor has an efficiency of e : 0.76. = M Prob. R14-6 B

If d = 0.72 ft and the spring has an unstretched length of 0.85 ft , determine the force F required for equilibrium

4 m M = (30t²) N•m F = 15t N. If the rod of negligible mass is subjected to a couple moment of M=29t2 N;M where t is the time in seconds, and the engine of the car supplies a braking force F= 15t N to the wheels, determine the speed of the car at t= 8s. The car at t=0s a a speed of 7 m/s. The total mass of the car and the driver is 158 kg. Neglect the size of the car.

15-51. The 30-Mg freight car A and 15-Mg freight car B are moving towards each other with the velocities shown. Determine the maximum compression of the spring mounted on car A. Neglect rolling resistance