MCQ
$A$ rod is hinged at its centre and rotated by applying a constant torque starting from rest. The power developed by the external torque as a function of time is :
- A
- ✓
- C
- D
✓
Answer
Correct option: B.
b
$P=\tau, \omega \Rightarrow P=\tau \alpha t \Rightarrow P=\tau, \frac{\tau}{I} t \Rightarrow P=\frac{\tau^{2}}{I} t \Rightarrow P \propto t$
$P=\tau, \omega \Rightarrow P=\tau \alpha t \Rightarrow P=\tau, \frac{\tau}{I} t \Rightarrow P=\frac{\tau^{2}}{I} t \Rightarrow P \propto t$
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