MCQ
A body rotating with uniform angular acceleration covers $100 \pi$ (radian) in the first $5 \,s$ after the start. Its angular speed at the end of $5 \,s$ (in radian/s) is .........$\pi$
- ✓$40$
- B$30$
- C$20$
- D$10$
✓
Answer
Correct option: A.
$40$
a
(a)
(a)
Given, $\theta=100 \,\pi$ radians
$t=5\,s$
From the second equation of angular motion, $\theta=\frac{1}{2} at ^2$
$=100\,\pi=\frac{1}{2} \alpha \times 5^2$
$=8\,\pi rad / s ^2$
$\therefore \omega= at =8\,\pi \times 5=40\,\pi \text { radians }$
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