A stone tied to a string is whirled in a uniform circular path in a horizontal plane
PHYSICS · Single correct · A Level · Physics · Mechanics and materials · Mechanics and materials
Problem
A stone tied to a string is whirled in a uniform circular path in a horizontal plane. What is the work done by the tension in the string after the stone completes half a revolution?
(a) Positive and equal to the change in kinetic energy
(b) Zero because the tension is always perpendicular to the displacement
(c) Tπr where T is the tension and r is the radius of the circle
(d) Cannot be determined without knowing the speed