MCQ
A particle revolves with constant angular acceleration $\pi\, rad/s^2$. If the particle starts from rest, how many revolution will it make in the first $10\, seconds$ ?
- A$16$
- B$10$
- C$20$
- ✓$25$
✓
Answer
Correct option: D.
$25$
d
$\alpha=\pi \operatorname{rad} / \mathrm{s}^{2}$
$\alpha=\pi \operatorname{rad} / \mathrm{s}^{2}$
$\theta=\omega_{0} t+\frac{1}{2} \alpha t^{2}$
$\omega_{0}=0$
$\therefore \quad \theta=\frac{1}{2} \alpha t^{2}$
$2 \mathrm{n} \pi=\frac{1}{2} \propto \mathrm{t}^{2}$
$2 \mathrm{n} \pi=\frac{1}{2}(\pi)(10)^{2}$
$\mathrm{x}=25$
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