Free Electronics MCQs with Answers
660 Electronics MCQs from Physics, each with the correct answer and a written explanation of why it is correct. Free and unlimited, with no account needed.
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 9 of 33
- A. Covalent bond
- B. Ionic bond
- C. Molecular bond
- D. None of these
Explanation: As silicon is a non metal all of its valence electrons will form covalent bonds by sharing if electrons to fill their outermost shells and…
Correct answer: Covalent bond- A. Protons
- B. Electrons
- C. Positrons
- D. Holes
Explanation: The majority charge carriers in the P-type region of a p-n junction are "holes."
Correct answer: Holes- A. 1:106
- B. 1:104
- C. 1:108
- D. 1:1010
Explanation: Germanium is a semiconductor having an indirect bandgap, as is crystalline silicon.
Correct answer: 1:108- A. Silicon
- B. Germinium
- C. Indium
- D. Gallium
Explanation: At room temperature, Silicon crystal has fewer free electrons than Germanium , Indium and gallium crystal.
Correct answer: Silicon- A. Negative ions
- B. Positive ions
- C. Both positive and negative ions
- D. None of these
Explanation: In a p-n junction, when a depletion region is formed due to the diffusion of majority carriers (holes in the p-region and electrons in the…
Correct answer: Both positive and negative ions- A. Free electrons in n region
- B. Holes in p-region
- C. Both free electrons and holes
- D. None of these
Explanation: When a p-n junction diode is forward biased, i.e. forward biasing voltage V is applied to the diode, this potential difference reduces the…
Correct answer: Both free electrons and holes- A. Does not change
- B. Decreases
- C. Also increases
- D. None of these
Explanation: When a diode is forward biased, increasing the applied voltage increases the current flowing through it.
Correct answer: Also increases168. While drawing a graph between current and biasing voltage in p-n junction the current is taken:
- A. Along x-axis
- B. Along -y-axis
- C. Along x-axis and in mA
- D. Along +y-axis
Explanation: The x-axis represents the biasing voltage, and the current is plotted along the y-axis.
Correct answer: Along x-axis and in mA- A. A few MΩ
- B. Several MΩ
- C. A few ohms
- D. None of these
Explanation: When a p-n junction is reverse biased, it acts as a high resistance path for current flow. The resistance is typically several MΩ.
Correct answer: Several MΩ- A. Two way conduction
- B. Zero conduction
- C. One way conduction
- D. Amplification
Explanation: A semiconductor diode is a device that permits the flow of electric current in only one direction and is made from a silicon or germanium…
Correct answer: One way conduction- A. Majority carriers
- B. Minority carriers
- C. Dual carriers
- D. None of these
Explanation: Electrons are minority charge carriers in p type semiconductors. In an intrinsic semiconductor, some of the electrons in the valence band…
Correct answer: Minority carriers- A. n
- B. P
- C. Both n and P
- D. Any of above
Explanation: N-type semiconductors are created by doping an intrinsic semiconductor with an electron donor element during manufacture.
Correct answer: n- A. Capacitor
- B. Inductor
- C. On switch
- D. Off switch
Explanation: A p-n junction diode acts as an off switch when operating in a reverse-biased region.
Correct answer: Off switch- A. Holes as majority carrier
- B. Immobile positive ions
- C. Immobile negative ions
- D. None of these
Explanation: In an N-type semiconductor, the density of negative charge carriers is higher; therefore, it has immobile positive ions, and electrons are…
Correct answer: Immobile positive ions- A. Increase with inverse biasing
- B. Decrease with light doping
- C. Increase with heavy doping
- D. None of these
Explanation: The depletion region width on each side of the p-n junction inversely varies with the dopant concentration.
Correct answer: Increase with inverse biasing- A. Conductor
- B. Semi conductor
- C. Insulator
- D. None of these
Explanation: CONCEPT:Conductor: The material that allows the electric current to flow through them easily is called a conductor.Example: Metals like…
Correct answer: Insulator- A. Conductors
- B. Semi conductors
- C. Insulators
- D. None of these
Explanation: CONCEPT:Conductor: The material that allows the electric current to flow through them easily is called a conductor.Example: Metals like…
Correct answer: Conductors- A. Protons
- B. Electrons
- C. Neutrons
- D. Holes
Explanation: In the n-type semiconductor, electrons are the majority carriers, and holes the minority carriers
Correct answer: Holes- A. Protons
- B. Electrons
- C. Neutrons
- D. Holes
Explanation: In a p-type semiconductor, the majority carriers are holes, and the minority carriers are electrons
Correct answer: Electrons- A. An amplifier
- B. An oscillator
- C. A detector
- D. A semi conductor diode
Explanation: P-N junction diode is a basic semiconductor device that is widely used in electronic circuits.
Correct answer: A semi conductor diode