COMEDK · Physics · 19. Current Electricity
On increasing the temperature of a conductor, its resistance increases because
- A Electron density decreases
- B Relaxation time decreases
- C Number of collisions between electrons decreases
- D Relaxation time increases
Answer & Solution
Correct Answer
(B) Relaxation time decreases
Step-by-step Solution
Detailed explanation
The resistance of a conductor is given by the formula \(R = \dfrac{ml}{ne^{2}A\tau}\), where \(m\) is the mass of the electron, \(l\) is the length of the conductor, \(n\) is the number density of free electrons, \(e\) is the charge of the electron, \(A\) is the cross-sectional…
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