Free Electronics MCQs with Answers
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A p-n junction forms when p-type and n-type semiconductor regions meet, creating a depletion layer, barrier potential and rectifying action. The work covers forward and reverse bias, junction current, diode characteristics, and how a diode converts alternating current into pulsating direct current through half-wave and full-wave rectification.
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Read the Electronics notesFree MDCAT chapter notes with key terms660 questions · page 5 of 33
- A. the emitter base junction is forward biased and the collector base junction is reverse biased
- B. no bias voltage is required
- C. both junctions are forward biased
- D. both junctions are reverse biased
Explanation: To use a transistor as an amplifier, the emitter-base junction is forward biased, allowing the injection of carriers from the emitter to…
Correct answer: the emitter base junction is forward biased and the collector base junction is reverse biased- A. holes are the only carriers
- B. electrons are the only carriers
- C. holes are the majority carriers and electrons are the minority carriers
- D. electrons are the majority carriers and holes are the minority carriers
Explanation: on: (c) holes are the majority carriers and electrons are the minority carriersExplanation: In a p-type semiconductor, majority carriers…
Correct answer: holes are the majority carriers and electrons are the minority carriers- A. 500
- B. 250
- C. 125
- D. 75
Explanation: The current gain (β) of a transistor is given by the ratio of collector current (IC ) to base current (IB ).
Correct answer: 250- A. OR
- B. AND
- C. NOT
- D. NAND
Explanation: The NOT gate, also known as an inverter, has only one input terminal. It produces an output that is the logical opposite (complement) of…
Correct answer: NOT- A. Vo=+Vcc
- B. Vo = - Vcc
- C. V = V-
- D. Vo = V+
Explanation: In a comparator, when the inverting input (V− ) is less than the non-inverting input (V+ ), the output (Vo ) is typically at the negative…
Correct answer: Vo = - Vcc- A. are available universally
- B. can be combined to produce OR, AND, and NOT gate
- C. are widely used in integrated circuit packages
- D. are easiest to manufacture
Explanation: NAND and NOR gates are called universal gates because any logic function can be realized using combinations of either NAND gates or NOR…
Correct answer: can be combined to produce OR, AND, and NOT gate- A. increases
- B. decreases
- C. remains the same
- D. may increase or decrease depending upon the material
Explanation: With an increase in temperature, the potential barrier in a semiconductor junction decreases.
Correct answer: decreases- A. one
- B. two
- C. three
- D. four
Explanation: A bridge rectifier circuit typically employs four diodes arranged in a bridge configuration to convert alternating current (AC) to direct…
Correct answer: four- A. forward biased
- B. reverse biased
- C. no biasing
- D. none of these
Explanation: A photodiode is typically operated in reverse bias to create a depletion region where light-generated charge carriers can be collected.
Correct answer: reverse biased- A. its forward biased
- B. its reverse biased
- C. type of semiconductor material used
- D. type of doping
Explanation: The color of a Light Emitting Diode (LED) primarily depends on the semiconductor material used in its construction.
Correct answer: type of semiconductor material used- A. OR
- B. NAND
- C. XOR
- D. All
Explanation: a) OR: An OR gate produces an output of 1 when at least one input is 1.
Correct answer: All- A. 10^-2 m
- B. 10^-4 m
- C. 10^-5 m
- D. 10^-6 m
Explanation: The base region of a transistor is typically on the order of micrometers (10^−6 m) or sub-micrometers (10^−4 m).
Correct answer: 10^-5 m- A. inverting input and ground terminal
- B. non-inverting input and ground
- C. output terminal and ground
- D. Input and output terminal
Explanation: The output resistance of an operational amplifier is primarily determined by the resistance between the output terminal and ground.
Correct answer: output terminal and ground- A. inverting amplifier
- B. non-inverting amplifier
- C. comparator
- D. All of these
Explanation: Operational amplifiers (op-amps) are versatile devices and can be used for various applications, including inverting and non-inverting…
Correct answer: All of these- A. germanium
- B. silicon
- C. gallium
- D. aluminium
Explanation: Silicon is the most commonly used semiconductor material in the electronics industry.
Correct answer: silicon- A. diffused region
- B. depletion region
- C. p-region
- D. n-region
Explanation: The depletion region is the region in a p-n junction where charge carriers (electrons and holes) are depleted or absent due to the…
Correct answer: depletion region- A. diffusion
- B. fusion
- C. emission
- D. fission
Explanation: The depletion region is formed around the junction by the process of diffusion.
Correct answer: diffusion- A. A.C
- B. D.C
- C. both a &
- D. none of these
Explanation: In the process of rectification, the alternating current (A.C) is converted into direct current (D.C).
Correct answer: D.C- A. A.C
- B. D.C
- C. both a & b
- D. none of these
Explanation: In the process of rectification, the alternating current (A.C) is converted into direct current (D.C).
Correct answer: D.C- A. cherry colour
- B. yellow colour
- C. red colour
- D. dull red colour
Explanation: When platinum is heated at around 1300°C, it emits a bright red light, which appears as a cherry color.
Correct answer: cherry colour