MCQ
The angular speed of a fly-wheel making $120\, revolution/minute$ is
- A$\pi \,rad/sec$
- B$2$ $\pi \,rad/sec$
- ✓$4$ $\pi\, rad/sec$
- D$4$ $\pi^2\,rad/sec$
✓
Answer
Correct option: C.
$4$ $\pi\, rad/sec$
c
$120 rev$ $/ \min =120 \times 2 \pi / 60 \mathrm{rad} / \mathrm{sec}=4 \pi \mathrm{rad} / \mathrm{sec}$
$120 rev$ $/ \min =120 \times 2 \pi / 60 \mathrm{rad} / \mathrm{sec}=4 \pi \mathrm{rad} / \mathrm{sec}$
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