Question
A body rotates about a fixed axis with an angular acceleration of $3 \,rad / s ^2$. The angle rotated by it during the time when its angular velocity increases from $10 \,rad / s$ to $20 \,rad / s$ (in radian) is ..........
✓
Answer
(a)
Given $\alpha = 3$
$w_2^2=w_1^2+2 \alpha \theta$
$\Rightarrow (20)^2=(10)^2+2 \times 3 \theta$
$\Rightarrow \frac{300}{6}=\theta$
$\Rightarrow \theta=50 \text { radian. }$
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