Question

A customer service person in a department store is wrapping packages for customers. The ribbon spool she uses has 13.7 m of ribbon wound on it. The radius of the spool is 13.0 cm and its moment of inertia is 0.41 kg · m². As the spool turns, friction forces cause a torque of 0.19 N · m to act on it. The spool is initially at rest. The service person pulls on the spool with a constant tension of 13.0 N. Determine the time it takes, in seconds, to unwind 5.5 m of the ribbon, assuming there is no slippage and the mass of the ribbon is negligible.

Answer 1