Q.1 Which of the following is an intrinsic semiconductor?
Silicon
Germanium doped with Arsenic
Copper
Aluminum
Explanation - An intrinsic semiconductor is a pure semiconductor without any significant dopant atoms. Silicon in its pure form is an intrinsic semiconductor.
Correct answer is: Silicon
Q.2 What type of charge carriers dominate in a p-type semiconductor?
Electrons
Holes
Protons
Neutrons
Explanation - In a p-type semiconductor, the majority carriers are holes created by acceptor doping.
Correct answer is: Holes
Q.3 What is the main purpose of doping in semiconductors?
To increase thermal conductivity
To change electrical conductivity
To make it magnetic
To make it transparent
Explanation - Doping introduces impurities into a semiconductor to increase its electrical conductivity.
Correct answer is: To change electrical conductivity
Q.4 Which junction in a diode allows current to flow only in one direction?
PN junction
NP junction
PP junction
NN junction
Explanation - A PN junction diode conducts current in forward bias and blocks in reverse bias, allowing unidirectional flow.
Correct answer is: PN junction
Q.5 What is the typical forward voltage drop across a silicon diode?
0.3 V
0.7 V
1.2 V
2.0 V
Explanation - A silicon diode typically has a forward voltage drop of about 0.7 volts when conducting.
Correct answer is: 0.7 V
Q.6 Which type of transistor is widely used as a switch in digital circuits?
BJT
FET
MOSFET
All of the above
Explanation - BJTs, FETs, and MOSFETs can all be used as electronic switches, though MOSFETs are most common in modern digital circuits.
Correct answer is: All of the above
Q.7 In an NPN transistor, what type of carriers move from the emitter to the collector?
Electrons
Holes
Protons
Neutrons
Explanation - In an NPN transistor, electrons are the majority carriers flowing from the emitter to the collector.
Correct answer is: Electrons
Q.8 Which parameter of a transistor determines its amplification capability?
β (beta)
VBE
IC
IE
Explanation - The current gain β (beta) of a transistor is the ratio of collector current to base current and determines its amplification capability.
Correct answer is: β (beta)
Q.9 Which semiconductor device is used for voltage regulation?
Zener diode
LED
Photodiode
BJT
Explanation - A Zener diode is designed to operate in reverse breakdown mode and is commonly used for voltage regulation.
Correct answer is: Zener diode
Q.10 What is the main advantage of a MOSFET over a BJT?
Higher input resistance
Lower switching speed
Higher power consumption
Lower voltage drop
Explanation - MOSFETs have very high input resistance, which makes them ideal for voltage-controlled switching applications.
Correct answer is: Higher input resistance
Q.11 Which of the following is a type of FET?
JFET
PNP transistor
BJT
SCR
Explanation - JFET (Junction Field Effect Transistor) is a type of FET, where current is controlled by voltage applied to the gate terminal.
Correct answer is: JFET
Q.12 Which logic gate gives output HIGH only when all inputs are HIGH?
OR
AND
NAND
NOR
Explanation - An AND gate outputs HIGH only if all its inputs are HIGH; otherwise, output is LOW.
Correct answer is: AND
Q.13 Which device converts light energy into electrical energy?
LED
Photodiode
Zener diode
BJT
Explanation - A photodiode generates current when exposed to light and is used in optical sensors.
Correct answer is: Photodiode
Q.14 What is the main function of a capacitor in an electronic circuit?
Store energy
Amplify current
Convert AC to DC
Switch current
Explanation - A capacitor stores electrical energy in the form of an electric field and can release it when required.
Correct answer is: Store energy
Q.15 Which semiconductor device is used as a rectifier?
Diode
Transistor
MOSFET
LED
Explanation - A diode allows current to flow in one direction, making it suitable for converting AC to DC.
Correct answer is: Diode
Q.16 What type of diode emits light when forward biased?
Zener diode
LED
Photodiode
Tunnel diode
Explanation - A Light Emitting Diode (LED) emits light when a forward voltage is applied across it.
Correct answer is: LED
Q.17 Which electronic component opposes change in current?
Capacitor
Inductor
Resistor
Diode
Explanation - An inductor resists changes in current by inducing a voltage opposing the change, storing energy in a magnetic field.
Correct answer is: Inductor
Q.18 What is the main advantage of a Schottky diode over a normal PN junction diode?
Lower forward voltage drop
Higher breakdown voltage
Emits light
Amplifies current
Explanation - Schottky diodes have lower forward voltage drop (~0.2-0.3 V) compared to silicon diodes (~0.7 V), making them faster and more efficient.
Correct answer is: Lower forward voltage drop
Q.19 In digital electronics, what is the binary equivalent of decimal 10?
1010
1100
1001
1110
Explanation - The decimal number 10 is represented as 1010 in binary.
Correct answer is: 1010
Q.20 Which device is used to amplify weak electrical signals?
Transistor
Diode
LED
Resistor
Explanation - A transistor can amplify current or voltage, making it suitable for amplifying weak electrical signals.
Correct answer is: Transistor
Q.21 Which component is used to store charge in a circuit?
Resistor
Capacitor
Inductor
Diode
Explanation - A capacitor stores electrical charge and can release it when needed.
Correct answer is: Capacitor
Q.22 Which type of semiconductor has been doped with donor atoms?
N-type
P-type
Intrinsic
None of these
Explanation - N-type semiconductors are doped with donor atoms that provide extra electrons as majority carriers.
Correct answer is: N-type
Q.23 What is the function of the gate in a MOSFET?
Control current flow between source and drain
Supply power
Act as resistor
Emit light
Explanation - The gate voltage controls the conductivity of the channel between source and drain in a MOSFET.
Correct answer is: Control current flow between source and drain
Q.24 Which logic gate outputs LOW only when all inputs are HIGH?
AND
OR
NAND
NOR
Explanation - A NAND gate is the complement of an AND gate; it outputs LOW only if all inputs are HIGH.
Correct answer is: NAND
Q.25 What type of diode is used in high-speed switching applications?
Schottky diode
Zener diode
LED
Photodiode
Explanation - Schottky diodes have low forward voltage drop and fast switching speed, suitable for high-speed applications.
Correct answer is: Schottky diode