MCQ
On increasing the temperature of a conductor, its resistance increases because
- ✓Relaxation time decreases
- BMass of the electrons increases
- CElectron density decreases
- DNone of the above
✓
Answer
Correct option: A.
Relaxation time decreases
(a) Resistance of conductor depends upon relation as $R \propto \frac{1}{\tau}$. With rise in temperature $r m s$ speed of free electron inside the conductor increase, so relaxation time decrease and hence resistance increases
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