MCQ set for Physics class 12 term 2 examination [2022]

Last updated on March 26th, 2023 at 04:04 pm

This is a MCQ set for Physics Class 12 Term 2 examination [2022] covering the Semiconductor Physics chapter. (CBSE board, ISC board)

Physics Class 12 Term 2 examination [2022] MCQ set on Semiconductor Physics

1 ) The conductivity of a semiconductor increases with increase in temperature, because [NCERT Exemplar]
(a) number density of free current carriers increases
(b) relaxation time increases
(c) Both number density of carriers and relaxation time increase
(d) number density of carriers increases, relaxation time decreases but effect of decrease in relaxation time is much less than increase in number density

2 ) Which of the following correctly represents the hole in semiconductor?
(a) An anti-particle of electron
(b) A vacancy created when an electron leaves a covalent bond
(c) Absence of free electrons
(d) An artificially created particle

3 ) The substance which is doped in an intrinsic semiconductor to make p-type semiconductor is
(a) phosphorus (b) antimony
(c) aluminium (d) arsenic

4 ) In n-type semiconductor, electrons are majority charge carriers but it does not show any negative charge. The reason is
(a) electrons are stationary
(b) electrons neutralise with holes
(c) mobility of electrons is extremely small
(d) atom is electrically neutral

5) When an electric field is applied across a semiconductor,
(a) electrons move from lower energy level to higher energy
level in the conduction band
(b) electrons move from higher energy level to lower energy
level in the conduction band
(c) holes in the valence band move from lower energy level
to higher energy level
(d) None of the above

6) The barrier potential of a p-n junction depends on [CBSE 2014]
(i) type of semiconductor material
(ii) amount of doping
(iii) temperature

Which one of the following is correct?
(a) Both (i) and (ii) (b) Only (ii)
(c) Both (ii) and (iii) (d) (i), (ii) and (iii)

7) A 220 V AC supply is connected between points A and B (figure). What will be the potential difference across the capacitor? [NCERT Exemplar]

(a) 220 V (b) 110 V
(c) 0 V (d) 220 (2)^1/2 V

8) The output of the given circuit in figure given below [NCERT Exemplar]

(a) would be zero at all times
(b) would be like a half-wave rectifier with positive cycles in output

(c) would be like a half-wave rectifier with negative cycles in
output
(d) would be like that of a full wave rectifier

9)

The wavelength and intensity of light emitted by a LED depend upon
(a) forward bias and energy gap of the semiconductor
(b) energy gap of the semiconductor and reverse bias
(c) energy gap only
(d) forward bias only

10)

The I-V characteristic of an LED is

Answers to MCQ set 1 (semiconductors) – class 12 term 2 Physics – In the next page (link below)