NEET Physics Semiconductor Electronics MCQs Set A

a) number density of carries increases, relaxation time decreases but effect of decrease in relaxation time is much less than increase in number density

b) both number density of carries and relaxation time increase

c) relaxation time increases

d) number density of free current carries increases

Answer: number density of carries increases, relaxation time decreases but effect of decrease in relaxation time is much less than increase in number density

Question:  The barrier potential of a p-n junction depends on:
(A) type of semi conductor material
(B) amount of doping
(C) temperature
Which one of the following is correct ?

a) (A), (B) and (C)

b) (B) only

c) (B) and (C) only

d) (A) and (B) only

Answer:  (A), (B) and (C)

Question:  An oscillator is nothing but an amplifier with

a) positive feedback

b) large gain

c) negative feedback

d) no feedback

Answer:  positive feedback

More Questions..................................... 

Question: Assertion : A transistor amplifier in common emitter configuration has a low input impedence.
Reason : The base to emitter region is forward biased

a) If both Assertion and Reason are correct and Reason is the correct explanation of Assertion.

b) If both Assertion and Reason are correct, but Reason is not the correct explanation of Assertion

c) If Assertion is correct but Reason is incorrect.

d) If both the Assertion and Reason are incorrect.

Answer: If both Assertion and Reason are correct and Reason is the correct explanation of Assertion.

Question: The temperature dependence of resistances of Cu and undoped Si in the temperature range 300-400 K, is best described by

a) Linear increase for Cu, exponential decrease of Si.

b) Linear decrease for Cu, linear decrease for Si.

c) Linear increase for Cu, linear increase for Si.

d) Linear increase for Cu, exponential increase for Si.

Answer:  Linear increase for Cu, exponential decrease of Si.