Question

A constant torque of $31.4\, Nm$ is exerted on a pivoted wheel. If angular acceleration of wheel is $4\pi\,rad\,s^{-2}$, then the moment of inertia of w heel is

• A. $3.5\,kg\,m^2$
• B. $2.5\,kg\,m^2$
• C. $4.5\,kg\,m^2$
• D. $5.5\,kg\,m^2$

Answer 1

Answer: (B)

$2.5\,kg\,m^2$

Answer 2

$I \alpha = \tau \, i.e. \, I = \frac{\tau}{\alpha} = \frac{31.4}{4 \pi} = 2.5 \, kg \, m^2$