1. . A semiconductor has generally ……………… valence electrons.
(A) 2
(B) 3
(C) 6
(D) 4
2. . When a pentavalent impurity is added to a pure semiconductor, it becomes ……:
(A) An insulator
(B) An intrinsic semiconductor
(C) N-type semiconductor
(D) P-type semiconductor
3. . A pentavalent impurity has ………. Valence electrons
(A) 3
(B) 5
(C) 4
(D) 6
4. . A hole in a semiconductor is defined as …………….:
(A) A free electron
(B) Incomplete part of an electron pair bond
(C) A free proton
(D) A free neutron
5. . A PN junction acts as a ……….
(A) Controlled switch
(B) Bidirectional switch
(C) Unidirectional switch
(D) None of the above
6. . Number of electrons in outer most shell of conducting material is:
(A) Less than 4
(B) Always 4
(C) More than 4
(D) 8
7. . In a P-N junction, the potential barrier is due to the charges on either side of the junction. These charges are:
(A) Majority carriers
(B) Minority carriers
(C) Both (a) & (b)
(D) Fixed donor and acceptor ions
8. . The process of applying an external voltage to diode is called as:
(A) Biasing
(B) Rectification
(C) Doping
(D) None of these
9. . Under normal conditions a diode conducts current when it is…
(A) Reverse biased
(B) Forward biased
(C) Avalanched
(D) Saturated
10. . A filter circuit which converts the pulsating DC of rectifier output into:
(A) AC
(B) AC & DC
(C) Smooth DC
(D) None of these
11. . The part of DC power supply:
(A) Transformer
(B) Filter
(C) Sub Station
(D) Both a & b
12. . Full wave bridge rectifier circuit has …….diodes.
(A) 4
(B) 2
(C) 6
(D) 8
13. . T filter consists on:
(A) A capacitor and an inductor
(B) single inductor
(C) A capacitor and two inductors
(D) Two capacitors