The Drum Shown in the Figure Has a Radius of 0.40

Multiple Choice

The drum shown in the figure has a radius of 0.40 m and a moment of inertia of 2.3 $\mathrm { kg } \cdot \mathrm { m } ^ { 2 }$ about an axis perpendicular to it through its center. The frictional torque at the drum axle is 3.0 N ? m. A 14-m length of rope is wound around the rim. The drum is initially at rest. A constant force is applied to the free end of the rope until the rope is completely unwound and slips off. At that instant, the angular speed of the drum is $23 \mathrm { rad } / \mathrm { s }$ The drum then slows down at a constant rate and comes to a halt. In this situation, what was the magnitude of the constant force applied to the rope?

A) 51 N
B) 40 N
C) 29 N
D) 18 N
E) 7.5 N