# Physics: Kinetic energy applied to a roll of paper towel with force applied tangentially.

See attached file.

A roll of paper towels is a uniform hollow cylinder, mass M=.75 kg, outer radius Ro=.084 m, inside radius of the hollow core Ri=.036 m. The roll is mounted on frictionless bearings.

See attachment #1 for a picture showing parameters.

By pulling on the paper towel with a tangential force P=.25 nt, starting at rest, the roll is thus given initial angular acceleration Ao.

a. Find the kinetic energy of the rotating roll at the end of t= 5.2 seconds. (Assume that the outer radius does not change during this time.)

b. When exactly half of the roll has been removed, with the same force P applied tangentially, find the angular acceleration Af.

https://brainmass.com/physics/energy/kinetic-energy-applied-roll-paper-towel-force-5853

#### Solution Preview

See file attached.

Solution procedure: For your most benefit, follow the procedure given below before you look at the correct solution equations provided in attachment #2.

part a.

Step 1. Recall or develop the initial moment of ...

#### Solution Summary

The solution provides a step-by-step procedure to arrive at the answer, but also works the problem in an attachment.