1. A semiconductor’s conductivity increases with:
(A) Decreasing temperature
(B) Increasing temperature
(C) Applying reverse bias
(D) Reducing doping
2. The majority carriers in an N-type semiconductor are:
(A) Holes
(B) Electrons
(C) Ions
(D) Both holes and electrons equally
3. The majority carriers in a P-type semiconductor are:
(A) Holes
(B) Electrons
(C) Ions
(D) None of the above
4. Intrinsic semiconductors are:
(A) Pure semiconductors
(B) Doped semiconductors
(C) Metal conductors
(D) Insulators
5. Extrinsic semiconductors are:
(A) Pure semiconductors
(B) Doped semiconductors
(C) Metals
(D) Superconductors
6. Which type of doping adds electrons to a semiconductor?
(A) Acceptor doping
(B) Donor doping
(C) Compensation doping
(D) None
7. Which type of doping adds holes to a semiconductor?
(A) Donor doping
(B) Acceptor doping
(C) Compensation doping
(D) None
8. A PN junction is formed by:
(A) Joining P-type and N-type semiconductors
(B) Joining two P-type semiconductors
(C) Joining two N-type semiconductors
(D) Connecting metal and semiconductor
9. The depletion region of a PN junction:
(A) Contains free carriers
(B) Is free of mobile charge carriers
(C) Conducts heavily
(D) Acts as an inductor
10. Forward biasing a PN junction causes:
(A) Depletion region to widen
(B) Depletion region to shrink
(C) No change in depletion region
(D) Junction breakdown
11. Reverse biasing a PN junction causes:
(A) Depletion region to shrink
(B) Depletion region to widen
(C) Increased forward current
(D) Reduced barrier potential
12. A Zener diode operates in reverse breakdown to:
(A) Rectify AC
(B) Regulate voltage
(C) Amplify signal
(D) Switch current
13. The forward voltage drop of a silicon diode is approximately:
(A) 0.3 V
(B) 0.7 V
(C) 1.2 V
(D) 5 V
14. The forward voltage drop of a germanium diode is approximately:
(A) 0.3 V
(B) 0.7 V
(C) 1 V
(D) 1.5 V
15. Schottky diodes are characterized by:
(A) High forward voltage drop
(B) Low forward voltage drop and fast switching
(C) High leakage current
(D) Voltage regulation
16. LEDs emit light due to:
(A) Thermal radiation
(B) Recombination of electrons and holes
(C) External illumination
(D) Reverse bias
17. A photodiode is mainly used for:
(A) Light emission
(B) Detecting light
(C) Switching only
(D) Amplification
18. The main difference between a BJT and a FET is:
(A) BJT is voltage-controlled; FET is current-controlled
(B) BJT is current-controlled; FET is voltage-controlled
(C) Both are voltage-controlled
(D) Both are current-controlled
19. The gate terminal of a FET controls:
(A) Source current
(B) Drain current
(C) Emitter current
(D) Collector current
20. The main advantage of MOSFET over BJT is:
(A) Low input impedance
(B) High input impedance
(C) Low gain
(D) High leakage
21. A varactor diode is used as:
(A) Rectifier
(B) Voltage-controlled capacitor
(C) Amplifier
(D) Light sensor
22. Tunnel diodes are mainly used for:
(A) Low-frequency amplification
(B) High-speed switching
(C) Voltage regulation
(D) Rectification
23. The depletion width in a PN junction increases with:
(A) Forward bias
(B) Reverse bias
(C) Constant current
(D) AC signal
24. A PIN diode is commonly used in:
(A) Switching and RF applications
(B) Voltage regulation
(C) Power amplification
(D) Current rectification only
25. In a JFET, the channel is controlled by:
(A) Base terminal
(B) Gate terminal
(C) Collector terminal
(D) Source terminal
26. The main carrier in a P-type semiconductor is:
(A) Electron
(B) Hole
(C) Proton
(D) Neutron
27. The main carrier in an N-type semiconductor is:
(A) Electron
(B) Hole
(C) Ion
(D) Photon
28. Avalanche breakdown occurs due to:
(A) High forward bias
(B) Impact ionization in reverse bias
(C) Temperature effects
(D) Light exposure
29. Zener breakdown occurs due to:
(A) Thermal energy
(B) Strong electric field in reverse bias
(C) Forward conduction
(D) Light absorption
30. The rectification process is performed by:
(A) Diodes
(B) Transistors
(C) Resistors
(D) Capacitors