Question 622: Centre of Mass and Rotational Motion

Question

A constant torque of $$100 \mathrm{~N} \mathrm{~m}$$ turns a wheel of moment of inertia $$300 \mathrm{~kg} \mathrm{~m}^2$$ about an axis passing through its centre. Starting from rest, its angular velocity after $$3 \mathrm{~s}$$ is :-

Accepted Answer

$$\begin{aligned} 	au & =\mathrm{I} \alpha \Rightarrow \alpha=\frac{	au}{\mathrm{I}}=\frac{100}{300}=\frac{1}{3} ~\mathrm{rad} / \mathrm{sec}^2 \ \omega_{\mathrm{i}} & =0 \ \omega_{\mathrm{f}} & =\omega_{\mathrm{i}}+\alpha \mathrm{t} \ & =0+\frac{1}{3} 	imes 3 \ \omega_{\mathrm{f}} & =1 ~\mathrm{rad} / \mathrm{sec}\end{aligned}$$

Answer

1 rad/s

Answer

5 rad/s

Answer

10 rad/s

Answer

15 rad/s

Centre of Mass and Rotational Motion

A constant torque of $100 \mathrm{~N} \mathrm{~m} turns a wheel of moment of inertia 300 \mathrm{~kg} \mathrm{~m}^2 about an axis passing through its centre. Starting from rest, its angular velocity after 3 \mathrm{~s}$ is :-

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