MCQ
If angular velocity of a disc depends an angle rotated $\theta$ as $\omega = \theta ^2 + 2\theta$ , then its angular acceleration $\alpha$ at $\theta = 1$ $rad$ is ......... $ rad/sec^2$.
- A$8$
- B$10$
- ✓$12$
- DNone
✓
Answer
Correct option: C.
$12$
c
Given omrga $=\theta^{2}+2 \theta$
Given omrga $=\theta^{2}+2 \theta$
$\frac{d \omega}{d t h \eta}=2 \theta+2$
$\alpha=\omega \frac{d \omega}{d t h \eta}=\left(\theta^{2}+2 \theta\right)(2 \theta+2)$
at $\theta=1$
$\alpha=12 r a d / \sec ^{2}$
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