Question

A cord is wound round the circumference of wheel of radius `r`. The axis of the wheel is horizontal and fixed and moment of inertia about it is `I`. A weight `mg` is attached to the end of the cord and falls from rest. After falling through a distance `h`, the angular velocity of the wheel will be.
A. `sqrt((2 gh)/(I + mr))`
B. `[(2 mgh)/(I + mr^2)]^(1/(2))`
C. `[(2 mgh)/(I +2 m)]^(1/(2))`
D. `sqrt(2 gh)`

Answer 1

Correct Answer - B
(b) `mgh = (1)/(2) mv^2 + (1)/(2) I omega^2, v = omega r`
`omega = sqrt((2 mgh)/(I + mr^2))`.
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