MCQ
When sand is poured on a rotating disc, its angular velocity will:
- ✓Decrease.
- BIncreases.
- CRemain constant.
- DNone of these.
✓
Answer
Correct option: A.
Decrease.
On pouring sand, mass increases and, therefore moment of inertia $I$ increases. As $(\text{I}\omega) =$ constant,
therefore, angular velocity $\omega$ decreases.
therefore, angular velocity $\omega$ decreases.
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