Question

EXAMPLE 9.7 AN UNWINDING CABLE I We wrap a light, nonstretching cable around a solid cylinder, of mass 50 kg and diameter 0.120 m, that rotates in frictionless bear- ings about a stationary horizontal axis (Fig. 9.16). We pull the free end of the cable with a constant 9.0-N force for a distance of 2.0 m; it turns the cylinder as it unwinds without slipping. The cylinder is initially at rest. Find its final angular speed and the final speed of the cable.

Why can you not solve the problem using constant angular acceleration equations? Please explain in detail w a diagram.

Answer 1

torque = (9)(0-06)=0-54 N-mat Moment of inertian = MR² = (50) (0.062 in I = 0.09 kg ni? : Angular acceleration -I = o = 6 700/s? Wico Angle turned = Are lenght radius = 2 = 100 rad 0.06 cusing w=we trao => wp= sao = 52x6x100 Tap = 20 reals) speed = of R=(20) (0.06) = 1.2 m/s Aus