A wheel is rotating freely with an angular speed on a shaft

PHYSICS · Single correct · A Level · Physics · Engineering physics · Engineering physics

Problem

A wheel is rotating freely with an angular speed

\omega

on a shaft. The moment of inertia of the wheel is

I

and the moment of inertia of the shaft is negligible. Another wheel of moment of inertia

3I

initially at rest is suddenly coupled to the same shaft. The resultant fractional loss in the kinetic energy of the system is : (1)

\frac{5}{6}

(2)

\frac{1}{4}

(3) 0 (4)

\frac{3}{4}