Assume a hypothetical wire in which free electron density changes… - Vidyadip

MCQ

Assume a hypothetical wire in which free electron density changes with temperature in proportionality $n\ \alpha \ T$ assuming $\tau $(Relaxation time of collision) and dimensions of wire remain unchanged with increasing temperature. Which one of the resistance $v/s$ temperature graph is true

✓
B
C
D

✓

Answer

Correct option: A.

a
$R = \left( {\frac{{2lm}}{{{e^2}\tau A}}} \right)\frac{1}{n}$

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