A thin-walled hoop (moment of inertia ) of mass and radius rests on a horizontal…
PHYSICS · Multi-part · AP · Physics C: Mechanics · Energy and Momentum of Rotating Systems · Energy and Momentum of Rotating Systems
Problem
A thin-walled hoop (moment of inertia I=MR2) of mass 1.2kg and radius 0.20m rests on a horizontal surface with sufficient roughness to allow rolling without slipping. A light string is wrapped around the hoop’s axle and is pulled horizontally with a constant force of 6.0N, exerted at the axle height. The string remains horizontal as it unwinds.
(a) Determine the magnitude of the hoop’s linear acceleration while the string is being pulled.
(b) Calculate the magnitude and direction of the static friction force exerted by the surface on the hoop during this motion.
(c) The coefficient of static friction between the hoop and the surface is 0.15. Verify whether the hoop will indeed roll without slipping under the applied force.