MCQ
When a ceiling fan is switched off its angular velocity reduces to $50 \%$ while it makes 36 rotations. How many more rotation will it make before coming to rest (Assume uniform angular retardation)
- A18
- ✓12
- C36
- D48
✓
Answer
Correct option: B.
12
(b) $v=\sqrt{3 g r}$ and $a=\frac{v^2}{r}=\frac{3 g r}{r}=3 g$
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