A potters wheel having a radius 052 m and a moment of inerti

A potter\'s wheel having a radius 0.52 m and a moment of inertia of 12.7 kg · m² is rotating freely at 53 rev/min. The potter can stop the wheel in7.0 s by pressing a wet rag against the rim and exerting a radially inward force of 73 N. Find the effective coefficient of kinetic friction between the wheel and the wet rag.

Solution

= /t

= 53(2/60)/7 =

0.792 rad/sec²

Q = I* =

12.7 * 0.792

= 10.05 Nm

Ff = µFn

= Q/r =

10.05 / 0.52

= 19.32 N

Where Fn = applied force=73 N (Given)

µ = 19.32/ 73

= 0.264