1. . A semiconductor is formed by ……… bonds.
(A) Co-ordinate
(B) Electrovalent
(C) Covalent
(D) None of the above
2. . A semiconductor has ………… temperature coefficient of resistance.
(A) Positive
(B) Negative
(C) Zero
(D) None of the above
3. . The most commonly used semiconductor is ………..
(A) Germanium
(B) Carbon
(C) Silicon
(D) Sulphur
4. . When a pure semiconductor is heated, its resistance …………..
(A) Goes up
(B) Goes down
(C) Remains the same
(D) Can’t say
5. . When a pentavalent impurity is added to a pure semiconductor, it becomes ………
(A) An insulator
(B) An intrinsic semiconductor
(C) p-type semiconductor
(D) n-type semiconductor
6. . In a PN junction with no external voltage, the electric field between acceptor and donor ions is called a
(A) Peak
(B) Path
(C) Threshold
(D) Barrier
7. . In a PN junction the potential barrier is due to the charges on either side of the junction, these charges are
(A) Majority carriers
(B) Fixed donor and acceptor ions
(C) Both (a) and (b)
(D) Minority carriers
8. . When PN junction is in forward bias, by increasing the battery voltage
(A) Circuit resistance increases
(B) None of the above happens
(C) Current through P-N junction decreases
(D) Current through P-N junction increases
9. . The p-region has a greater concentration of __________ as compared to the n-region in a P-N junction.
(A) both holes & electrons
(B) electrons
(C) holes
(D) phonons
10. . Which of the below mentioned statements is false regarding a p-n junction diode?
(A) Diode are uncontrolled devices
(B) Diodes are rectifying devices
(C) Diodes are unidirectional devices
(D) Diodes have three terminals