When we apply the energy conversation principle to a cylinder rolling down an incline without sliding, we exclude the work done by friction because:
A)there is no friction present
B)the angular velocity of the center of mass about the point of contact is zero
C)the coefficient of kinetic friction is zero
D)the linear velocity of the point of contact (relative to the inclined surface)is zero
E)the coefficient of static and kinetic friction are equal

Question

Quizplus · Accepted Answer

The energy conservation principle can be applied without considering the work done by friction because the point of contact between the cylinder and the incline does not move relative to the inclined surface (i.e., its linear velocity is zero), indicating that there is no work done by friction in the direction of motion. This is characteristic of pure rolling motion, where static friction is present but does not do work because there is no relative sliding motion at the point of contact.

When We Apply the Energy Conversation Principle to a Cylinder