Electronics - Electrical Engineering (MCQ) questions and answers

1)   The P - type semiconductor impurities are also called as

a. Acceptor impurities
b. Donor impurities
c. Either (a) or (b)
d. None of these
Answer  Explanation 

ANSWER: Acceptor impurities

Explanation:
No explanation is available for this question!


2)   Impurities are generally added in the pure semiconductor to

a. increase the number of electrons
b. increase the number of holes
c. increase their conductivity
d. all of these
Answer  Explanation 

ANSWER: increase their conductivity

Explanation:
No explanation is available for this question!


3)   The cut - in voltage for silicon and germanium are

a. 0.3 V, 0.3 V
b. 0.3 V, 0.7 V
c. 0.7 V, 0.7 V
d. 0.7 V, 0.3 V
Answer  Explanation 

ANSWER: 0.7 V, 0.3 V

Explanation:
No explanation is available for this question!


4)   If an external electric field is applied across the intrinsic semiconductor, then the

a. More number of electron holes pair combination will be broken
b. More number of electron holes pair combination will be evolved
c. Less number of electron holes pair combination will be broken
d. Less number of electron holes pair combination will be evolved
Answer  Explanation 

ANSWER: More number of electron holes pair combination will be broken

Explanation:
No explanation is available for this question!


5)   The atomic number of silicon and germanium is

a. 32, 14
b. 12, 19
c. 14, 32
d. 19, 12
Answer  Explanation 

ANSWER: 14, 32

Explanation:
No explanation is available for this question!


6)   Filters are used to convert

a. Pulsating dc signal into a pure dc signal
b. Pure dc signal into a pulsating dc signal
c. Pulsating dc signal into a pure ac signal
d. Pulsating ac signal into a pure dc signal
Answer  Explanation 

ANSWER: Pulsating dc signal into a pure dc signal

Explanation:
No explanation is available for this question!


7)   In N - type semiconductor, the impurities added to a semiconductor are

a. Trivalent
b. Pentavalent
c. Monovalent
d. Tetravalent
Answer  Explanation 

ANSWER: Pentavalent

Explanation:
No explanation is available for this question!


8)   At low temperature, the semi conductor behaves as a

a. Perfect insulator
b. Perfect conductor
c. Perfect consulator
d. None of these
Answer  Explanation 

ANSWER: Perfect consulator

Explanation:
No explanation is available for this question!


9)   Valence electrons of silicon and germanium are

a. 2, 4
b. 4, 4
c. 4, 2
d. 2, 2
Answer  Explanation 

ANSWER: 4, 4

Explanation:
No explanation is available for this question!


10)   To move electrons from valence band to conduction band, the energy applied to the insulator is

a. Less than 15 eV
b. Equal to 15 eV
c. More than 15 eV
d. More than 25 eV
Answer  Explanation 

ANSWER: More than 15 eV

Explanation:
No explanation is available for this question!