The conductivity of a semiconductor increases with increase in temperature, because (a) Number density of free current carries increases (b) Relaxation time increases (c) Both number density of carries and relaxation time increase (d) Number density of carries increases, relaxation time decreases but effect of decrease in relaxation time is much less than increase in number density

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Physics NCERT Exemplar Solutions Class 12th Chapter Fourteen Physics Class 12th Semiconductor Electronics

The conductivity of a semiconductor increases with increase in temperature, because
(a) Number density of free current carries increases
(b) Relaxation time increases
(c) Both number density of carries and relaxation time increase
(d) Number density of carries increases, relaxation time decreases but effect of decrease in relaxation time is much less than increase in number density

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alok kumar singh | Contributor-Level 10

4 months ago

This is a Multiple Choice Questions as classified in NCERT Exemplar

Answer- (d)

Explanation- when we increase temperature conductivity increases because number density is increasing after increasing temperature which decreases the relaxation time

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