This quiz works best with JavaScript enabled. Home > Cbse > Class 12 > Science > Physics Part Ii > Class 12 Physics (Part Ii) Chapter 14 Semiconductor Electronics Materials – Quiz 6 🏠 Homepage 📘 Download PDF Books 📕 Premium PDF Books Class 12 Physics (Part Ii) Chapter 14 Semiconductor Electronics Materials Quiz 6 (60 MCQs) Quiz Instructions Select an option to see the correct answer instantly. 1. Which of the following materials has a very low conductivity when a voltage is applied? A) Mica. B) Silver. C) Copper. D) Aluminum. Show Answer Correct Answer: A) Mica. 2. Which semiconductor device is commonly used for rectification in power supplies? A) Transformer. B) Triac. C) Diodes. D) Inductor. Show Answer Correct Answer: C) Diodes. 3. In a semiconductor which of the following carries can contribute to the current? A) Electrons. B) Holes. C) Both. D) None. Show Answer Correct Answer: C) Both. 4. Why are IGBTs (Insulated Gate Bipolar Transistors) used in VFDs? A) They prevent current from flowing. B) They provide efficient, high-speed switching for AC motor control. C) They increase the weight of the motor. D) They generate resistance in circuits. Show Answer Correct Answer: B) They provide efficient, high-speed switching for AC motor control. 5. What is the amount of energy required to free an outer shell electron from its orbit to a free state? A) Band gap. B) Electron volt. C) Wavelength. D) Photovoltaic. Show Answer Correct Answer: A) Band gap. 6. Which of the following is a pentavalent impuity added while forming an extrinsic semiconductor? A) (a) Boron. B) Arsenic. C) Indium. D) Gallium. Show Answer Correct Answer: B) Arsenic. 7. Describe the role of a diode in electronic circuits. A) A diode acts as a resistor to limit current flow. B) A diode allows current to flow in one direction, controlling current flow and protecting circuits. C) A diode amplifies electrical signals in both directions. D) A diode stores electrical energy for later use. Show Answer Correct Answer: B) A diode allows current to flow in one direction, controlling current flow and protecting circuits. 8. In the forward bias arrangement of a p-n junction diode, A) The n-end is connected to the positive terminal of the battery. B) The p-end is connected to the positive terminal of the battery. C) The p-end is connected to the negative terminal of the battery. D) The direction of current is from n-end to p-end in the diode. Show Answer Correct Answer: B) The p-end is connected to the positive terminal of the battery. 9. In order to increase voltage, several solar cells are connected in ..... A) Inverters. B) Wires. C) Parallel. D) Series. Show Answer Correct Answer: D) Series. 10. What is a major limitation of vacuum tubes? A) High power consumption. B) High reliability. C) Low power consumption. D) Compact size. Show Answer Correct Answer: A) High power consumption. 11. What is the process of intentionally introducing impurities into a semiconductor to alter its electrical properties? A) Fusion. B) Doping. C) Melting. D) Crystallization. Show Answer Correct Answer: B) Doping. 12. Which among these is NOT the property of a semiconductor? A) Four electrons in the valence band forming covalent bonds. B) At 0 Kelvin semiconductor acts like an insulator. C) Semiconductors have two type of charge carriers. D) Semiconductors are temperature insensitive. Show Answer Correct Answer: D) Semiconductors are temperature insensitive. 13. Name three common semiconductor materials. A) Copper. B) Iron. C) Silicon, Germanium, Gallium Arsenide. D) Aluminum. Show Answer Correct Answer: C) Silicon, Germanium, Gallium Arsenide. 14. Choose the option that is not for the Trivalent impurities: A) *3 valence electrons. B) *produce p-type semiconductors. C) *producing a "hole" . D) Antimony, arsenic, and phosphorus are the examples. Show Answer Correct Answer: D) Antimony, arsenic, and phosphorus are the examples. 15. Electron occupying an energy level can be determined by A) Occupation function N(E). B) Normalized function F(E). C) Probability function F(E). D) Probability function Z(E). Show Answer Correct Answer: C) Probability function F(E). 16. What are the applications of transistors in modern electronics? A) Transistors are primarily used for mechanical movement. B) Transistors are designed for energy storage in batteries. C) Transistors are only used in radio broadcasting. D) Transistors are used in signal amplification, switching, voltage regulation, and as building blocks in integrated circuits for computers and other electronic devices. Show Answer Correct Answer: D) Transistors are used in signal amplification, switching, voltage regulation, and as building blocks in integrated circuits for computers and other electronic devices. 17. How does temperature affect the conductivity of semiconductors? A) Higher temperatures decrease conductivity. B) Conductivity is only affected by material type. C) Temperature increases conductivity in semiconductors. D) Temperature has no effect on conductivity. Show Answer Correct Answer: C) Temperature increases conductivity in semiconductors. 18. What are the different types of transistors and their applications? A) Darlington Transistor. B) Metal Oxide Semiconductor Field Effect Transistor (MOSFET). C) Silicon Controlled Rectifier (SCR). D) Bipolar Junction Transistor (BJT), Field Effect Transistor (FET), Insulated Gate Bipolar Transistor (IGBT). Show Answer Correct Answer: D) Bipolar Junction Transistor (BJT), Field Effect Transistor (FET), Insulated Gate Bipolar Transistor (IGBT). 19. What is the role of a diode in a rectifier circuit? A) To amplify the AC signal before rectification. B) To increase the voltage of the AC signal. C) To store energy for later use in the circuit. D) The role of a diode in a rectifier circuit is to convert AC to DC by allowing current to flow in one direction only. Show Answer Correct Answer: D) The role of a diode in a rectifier circuit is to convert AC to DC by allowing current to flow in one direction only. 20. What are the two types of doping in semiconductors? A) Positive doping and negative doping. B) X-type doping and y-type doping. C) A-type doping and b-type doping. D) N-type doping and p-type doping. Show Answer Correct Answer: D) N-type doping and p-type doping. 21. Semiconductor is A) Poor conductivity. B) Lies between conductivity and insulator. C) All the above. D) None of the above. Show Answer Correct Answer: B) Lies between conductivity and insulator. 22. The most commonly used semiconductor material is A) Indium. B) Germanium. C) Silicon. D) Phosphide. Show Answer Correct Answer: C) Silicon. 23. Describe the band theory of solids. A) The band theory of solids describes the distribution of energy levels in solids, explaining electrical conductivity through the concept of valence and conduction bands. B) The band theory is primarily concerned with the thermal properties of gases. C) The band theory explains the behavior of liquids in terms of molecular interactions. D) The band theory of solids focuses solely on the atomic structure of metals. Show Answer Correct Answer: A) The band theory of solids describes the distribution of energy levels in solids, explaining electrical conductivity through the concept of valence and conduction bands. 24. What are the key characteristics of a transistor when used as an amplifier? A) Key characteristics of a transistor as an amplifier include voltage gain, input/output impedance, operation in the active region, and ability to amplify AC signals. B) Requires no biasing for operation. C) Only suitable for digital signals. D) High thermal resistance. Show Answer Correct Answer: A) Key characteristics of a transistor as an amplifier include voltage gain, input/output impedance, operation in the active region, and ability to amplify AC signals. 25. The voltage at which the PN junctions brraks down and forward current suddenly start flowing is called: A) Reverse breakdown voltage. B) Cut-in Voltage. C) Peak inverse Voltage. D) None of the above. Show Answer Correct Answer: B) Cut-in Voltage. 26. What is the role of photons in semiconductor devices? A) Photons only contribute to the mechanical strength of semiconductor materials. B) Photons enable light absorption and emission, facilitating electrical current generation and light production in semiconductor devices. C) Photons are responsible for heat generation in semiconductors. D) Photons are used to increase the size of semiconductor devices. Show Answer Correct Answer: B) Photons enable light absorption and emission, facilitating electrical current generation and light production in semiconductor devices. 27. What was a significant factor in the transition from vacuum tubes to semiconductors? A) Advances in vacuum technology. B) Advances in solid-state physics. C) Higher power requirements. D) Increased size of devices. Show Answer Correct Answer: B) Advances in solid-state physics. 28. A semiconductor contains donor impurity atoms is callled as ..... semiconductor A) Intrinsic. B) N-type. C) P-type. D) Electron. Show Answer Correct Answer: B) N-type. 29. Transistors act like tiny " ..... " A) Switches. B) Bees?. C) Batteries. D) Electron sources. Show Answer Correct Answer: A) Switches. 30. In a three-phase motor drive system, how are semiconductors used? A) They help in mechanical alignment. B) They act as thermal insulators. C) They regulate voltage and current through switching devices like IGBTs. D) They increase the physical size of the motor. Show Answer Correct Answer: C) They regulate voltage and current through switching devices like IGBTs. 31. What was the first semiconductor device used in early radios? A) Transistor. B) Vacuum tube. C) Integrated circuit. D) Crystal detector. Show Answer Correct Answer: D) Crystal detector. 32. Heavily doped diode.2. Thin depletion region. 3. Sharp break down voltage All these are characteristics of which diode? A) PN diode. B) Zener Diode. C) Reversed biased diode. D) None of the above. Show Answer Correct Answer: B) Zener Diode. 33. In shunt voltage regulator transistor and zener diode are placed A) Parallel connection. B) Series connection. C) All the above. D) None of the above. Show Answer Correct Answer: A) Parallel connection. 34. How can diodes be used in protection circuits? A) Diodes protect circuits by preventing reverse polarity, clamping voltage spikes, and shunting excess voltage. B) Diodes increase current flow in circuits. C) Diodes are used to amplify signals in circuits. D) Diodes convert AC to DC in protection circuits. Show Answer Correct Answer: A) Diodes protect circuits by preventing reverse polarity, clamping voltage spikes, and shunting excess voltage. 35. What happens to electrons in semiconductors at absolute zero? A) They are bound to atoms. B) They flow freely. C) They are absent. D) They conduct electricity. Show Answer Correct Answer: A) They are bound to atoms. 36. How do diodes function in the rectification process? A) Diodes store electrical energy for later use in rectification. B) Diodes convert DC to AC in the rectification process. C) Diodes function by allowing current to flow in one direction, converting AC to DC in the rectification process. D) Diodes allow current to flow in both directions during rectification. Show Answer Correct Answer: C) Diodes function by allowing current to flow in one direction, converting AC to DC in the rectification process. 37. Which of the following has very low conductivity? A) Glass. B) Copper. C) Germanium. D) Silicon. Show Answer Correct Answer: A) Glass. 38. Explain the working of a P-N junction in semiconductors. A) The P-N junction only allows for one direction of current flow in semiconductors. B) The P-N junction increases resistance in semiconductors. C) The P-N junction allows for the control of current flow in semiconductors by using the built-in electric field to regulate the movement of charge carriers. D) The P-N junction has no effect on current flow in semiconductors. Show Answer Correct Answer: C) The P-N junction allows for the control of current flow in semiconductors by using the built-in electric field to regulate the movement of charge carriers. 39. Where can semiconductors be found? A) Only in smartphones and computers. B) Only in scientific laboratories. C) In solar panels and electric cars as well. D) Exclusively in gaming consoles. Show Answer Correct Answer: C) In solar panels and electric cars as well. 40. Explain the term 'quantum efficiency' in photonics. A) Quantum efficiency measures the temperature of a photonic device during operation. B) Quantum efficiency is the speed at which photons are emitted from a source. C) Quantum efficiency refers to the total energy output of a photonic device. D) Quantum efficiency is the measure of how effectively a photonic device converts absorbed photons into charge carriers. Show Answer Correct Answer: D) Quantum efficiency is the measure of how effectively a photonic device converts absorbed photons into charge carriers. 41. When a pentavalent impurity is added to a pure semiconductor, it becomes ..... A) P-type semiconductor. B) An insulator. C) An intrinsic semiconductor. D) N-type semiconductor. Show Answer Correct Answer: D) N-type semiconductor. 42. Potential barrier developed in a junction diode opposes the flow of A) Minority carrier in both regions only. B) Majority carriers only. C) Majority carriers only. D) Holes in p region. Show Answer Correct Answer: B) Majority carriers only. 43. Describe how a laser works. A) A laser generates light through chemical reactions in a gas. B) A laser creates light by heating a metal filament. C) A laser emits light by reflecting it off a prism. D) A laser produces a coherent beam of light through stimulated emission in an excited medium, amplified by mirrors. Show Answer Correct Answer: D) A laser produces a coherent beam of light through stimulated emission in an excited medium, amplified by mirrors. 44. What discovery in the 1930s showed promise for controlling charge flow? A) Diodes. B) Semiconductors. C) Vacuum Tubes. D) Transistors. Show Answer Correct Answer: B) Semiconductors. 45. Which of the following is a semiconductor? A) Brass. B) Plastic. C) Silicon. D) Copper. Show Answer Correct Answer: C) Silicon. 46. What is the purpose of doping in semiconductors? A) To improve the thermal conductivity of the material. B) To create a protective layer on the semiconductor surface. C) To reduce the size of semiconductor devices. D) The purpose of doping in semiconductors is to enhance their electrical conductivity by introducing charge carriers. Show Answer Correct Answer: D) The purpose of doping in semiconductors is to enhance their electrical conductivity by introducing charge carriers. 47. What is the purpose of a Schottky diode in electronic circuits? A) To increase the resistance in a circuit. B) To amplify weak signals in a circuit. C) The purpose of a Schottky diode is to provide fast switching and low forward voltage drop in electronic circuits. D) To store electrical energy for later use. Show Answer Correct Answer: C) The purpose of a Schottky diode is to provide fast switching and low forward voltage drop in electronic circuits. 48. What is the depletion region in a PN junction? A) A layer that enhances conductivity in the junction. B) A region where electrons and holes are abundant. C) The depletion region in a PN junction is a zone where charge carriers are depleted, resulting in an area with no free electrons or holes. D) A space filled with positive ions and negative charges. Show Answer Correct Answer: C) The depletion region in a PN junction is a zone where charge carriers are depleted, resulting in an area with no free electrons or holes. 49. Anode is ..... Polarity in diodes A) Positive. B) Ground. C) Hot Side. D) Negative. Show Answer Correct Answer: A) Positive. 50. What types of impurity atoms are added to increase the number of conduction-band electrons in intrinsic silicon? A) Octavalent. B) Pentavalent. C) Bivalent. D) Trivalent. Show Answer Correct Answer: B) Pentavalent. 51. If fermi levels is at mid of valence band and conduction band at absolute zero temperature then the material is: A) Conductor. B) Semiconductor. C) Insulator. D) None of the above. Show Answer Correct Answer: B) Semiconductor. 52. What is the role of the forbidden band gap in determining the conductivity of a material? A) Determines conductivity. B) No effect on conductivity. C) Decreases conductivity. D) Increases conductivity. Show Answer Correct Answer: C) Decreases conductivity. 53. What determines the behavior of doped semiconductors? A) Temperature. B) Magnetic Field. C) Charge Carriers. D) Voltage. Show Answer Correct Answer: C) Charge Carriers. 54. What is the difference between conductors and semiconductors? A) Conductors allow electricity to flow freely, while semiconductors can control the flow of electricity. B) Conductors are used in insulators, while semiconductors are used in conductors. C) Conductors have a higher resistance than semiconductors. D) Semiconductors can only conduct electricity at high temperatures, while conductors can do so at all temperatures. Show Answer Correct Answer: A) Conductors allow electricity to flow freely, while semiconductors can control the flow of electricity. 55. In intrinsic semiconductor at room temperature, the number of electrons and holes are: A) Different. B) Same. C) Zero. D) Infinite. Show Answer Correct Answer: B) Same. 56. What type of materials have electrical conductivity between that of insulators and conductors? A) Insulators. B) Semiconductors. C) Superconductors. D) Conductors. Show Answer Correct Answer: B) Semiconductors. 57. What is the significance of the Hall effect in semiconductors? A) The Hall effect measures the voltage across a conductor in a magnetic field only in metals. B) The Hall effect is primarily used for energy storage in semiconductor devices. C) The Hall effect enables measurement of charge carrier concentration and type in semiconductors. D) The Hall effect is used to increase the temperature of semiconductors. Show Answer Correct Answer: C) The Hall effect enables measurement of charge carrier concentration and type in semiconductors. 58. The ratio of majority and minority charge carriers in intrinsic semiconductors is unity A) True. B) False. C) All the above. D) None of the above. Show Answer Correct Answer: A) True. 59. The voltage across an LED is 1.5 V when it is in a circuit with 9 V battery and a 225 $\Omega$ resistor. What is the current through the resistor? A) 6.7 mA. B) 47 mA. C) 33 mA. D) 40 mA. Show Answer Correct Answer: C) 33 mA. 60. Solar cells first became a practical energy source for NASA for what application? A) Rovers. B) Space Shuttle. C) Rocket boosters. D) Satellites. Show Answer Correct Answer: D) Satellites. ← PreviousNext →Related QuizzesScience QuizzesClass 12 QuizzesClass 12 Physics (Part Ii) Chapter 14 Semiconductor Electronics Materials Quiz 1Class 12 Physics (Part Ii) Chapter 14 Semiconductor Electronics Materials Quiz 2Class 12 Physics (Part Ii) Chapter 14 Semiconductor Electronics Materials Quiz 3Class 12 Physics (Part Ii) Chapter 14 Semiconductor Electronics Materials Quiz 4Class 12 Physics (Part Ii) Chapter 14 Semiconductor Electronics Materials Quiz 5Class 12 Physics (Part Ii) Chapter 14 Semiconductor Electronics Materials Quiz 7Class 12 Physics (Part Ii) Chapter 10 Wave Optics QuizClass 12 Physics (Part Ii) Chapter 11 Dual Nature Of Radiation And Matter Quiz 🏠 Back to Homepage 📘 Download PDF Books 📕 Premium PDF Books