MCQ
If $I = 50\, kg-m^2$, then ......... $N-m$ torque will be applied to stop it in $10\, sec$. Its initial angular speed is $20\, rad/sec$.
- ✓$100$
- B$150$
- C$200$
- D$250$
✓
Answer
Correct option: A.
$100$
a
$\tau=\mathrm{I} \alpha=\frac{\mathrm{I} \Delta \mathrm{W}}{\Delta \mathrm{t}}=\frac{50(0-20)}{10}$
$\tau=\mathrm{I} \alpha=\frac{\mathrm{I} \Delta \mathrm{W}}{\Delta \mathrm{t}}=\frac{50(0-20)}{10}$
$\tau=-100 \mathrm{N}-\mathrm{m}$ means
$100 \mathrm{N}-\mathrm{m}$ in opposite to angular speed.
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