Electronic Devices Quiz - ICSE Class 12 Physics

Free practice quiz: Electronic Devices (ICSE Class 12 Physics). 46 multiple-choice questions with answers and explanations. Play online, no sign-up needed.

This ICSE Class 12 Physics practice quiz has 46 multiple-choice questions on Electronic Devices, and 46 of them come with an explanation. Try the 5 sample questions below (tap an option to check yourself), then play the full quiz online. No sign-up needed.

Sample questions

1. A p-n junction diode is forward biased. If the applied voltage is increased from $V_1$ to $V_2$ where $V_2 > V_1$, what happens to the barrier potential and the diffusion current?

   1. Barrier potential decreases, diffusion current increases
   2. Barrier potential increases, diffusion current decreases
   3. Barrier potential decreases, diffusion current decreases
   4. Barrier potential increases, diffusion current increases
   Show answer

   Answer: A. Barrier potential decreases, diffusion current increases

   In forward bias, the applied voltage opposes the internal barrier potential of the p-n junction. As the applied voltage increases, it effectively reduces the barrier potential, allowing more majority carriers to diffuse across the junction. This increased diffusion leads to a higher diffusion current. The drift current, due to minority carriers, remains relatively constant.

2. What is the primary function of a filter circuit in a DC power supply following a rectifier?

   1. To increase the output voltage
   2. To reduce the ripple in the DC output
   3. To convert DC to AC
   4. To regulate the input AC voltage
   Show answer

   Answer: B. To reduce the ripple in the DC output

   Rectifiers produce pulsating DC. Filter circuits, typically using capacitors and sometimes inductors, smooth out these pulsations (ripples) to provide a more steady and constant DC output voltage, making it suitable for powering electronic devices.

3. A Light Emitting Diode (LED) is essentially a forward-biased p-n junction that emits light due to:

   1. Blackbody radiation
   2. Bremsstrahlung effect
   3. Electroluminescence
   4. Photoelectric effect
   Show answer

   Answer: C. Electroluminescence

   Electroluminescence is the phenomenon where a material emits light in response to an electric current or field. In an LED, when the p-n junction is forward-biased, electrons and holes recombine in the depletion region, releasing energy in the form of photons (light). The color of the emitted light depends on the semiconductor material used.

4. A tunnel diode exhibits negative differential resistance due to:

   1. Thermal runaway
   2. Avalanche breakdown
   3. Quantum mechanical tunneling
   4. High doping concentration
   Show answer

   Answer: C. Quantum mechanical tunneling

   The negative differential resistance (NDR) characteristic of a tunnel diode arises from the quantum mechanical tunneling of electrons across a very narrow depletion region. As the forward voltage increases, the probability of tunneling initially increases, leading to a current rise, but then decreases as the energy levels for tunneling become misaligned.

5. Which semiconductor device is most suitable for use as a high-speed switch due to its extremely short switching time?

   1. Bipolar Junction Transistor (BJT)
   2. PN Junction Diode
   3. MOSFET
   4. SCR (Silicon Controlled Rectifier)
   Show answer

   Answer: C. MOSFET

   MOSFETs are generally considered to have faster switching times than BJTs, especially at very high frequencies. This is primarily because MOSFET switching is controlled by the movement of majority carriers and does not suffer from minority carrier storage effects, which slow down BJTs. SCRs are designed for power switching and are generally slower.

More questions in this quiz

Answers and explanations are in the full quiz.

1. A Zener diode is used as a voltage regulator. If the input voltage to the Zener diode circuit increases, what happens to the Zener current and the voltage across the Zener diode?
2. For a junction field-effect transistor (JFET), the transconductance ($g_m$) is defined as the change in drain current ($I_D$) with respect to the change in:
3. Which of the following semiconductor devices exhibits negative differential resistance (NDR)?
4. The depletion region in a p-n junction diode is formed due to:
5. For a bipolar junction transistor (BJT) operating in the active region, which of the following conditions must be met?
6. The figure of merit for a transistor amplifier is usually expressed in terms of:
7. In a MOSFET (Metal-Oxide-Semiconductor Field-Effect Transistor), the channel is formed between the source and the drain. The conductivity of this channel is controlled by:
8. A rectifier converts:
9. In a common-collector amplifier (also known as an emitter follower), the voltage gain is approximately:
10. The intrinsic semiconductor behavior changes to extrinsic when:
11. What is the main advantage of using a MOSFET over a BJT as a switch?
12. In a full-wave rectifier, the output frequency of the ripple is:
13. The threshold voltage ($V_{th}$) in a MOSFET refers to:
14. A photodiode is a semiconductor device that:
15. The process of doping a semiconductor with trivalent impurity atoms leads to the formation of:
16. In a common-base amplifier configuration, which terminal is common to both the input and output circuits?
17. Which type of semiconductor is formed by doping with pentavalent impurity atoms?
18. For a JFET in saturation region, the drain current ($I_D$) is primarily dependent on:
19. The 'punch-through' phenomenon in a BJT occurs when:
20. A varactor diode is a type of diode whose junction capacitance is:
21. The 'pinch-off' voltage ($V_P$) in a JFET is the gate-source voltage at which:
22. A bridge rectifier uses diodes to achieve:
23. In a transistor circuit operating in the active region, the collector current ($I_C$) is related to the emitter current ($I_E$) and base current ($I_B$) by the formula:
24. The purpose of a potentiometer in a transistor amplifier circuit is often to:
25. The beta ($\\beta$) of a transistor is defined as the ratio of:
26. Which of the following statements about MOSFETs is true?
27. The fundamental unit of an integrated circuit (IC) is:
28. In a series voltage regulator circuit, a Zener diode is used to:
29. The output characteristic curve of a BJT in the common-emitter configuration plots collector current ($I_C$) against:
30. A 'Schottky diode' is characterized by:
31. In a common-source amplifier configuration of a MOSFET, the input signal is applied to the:
32. The doping concentration in a semiconductor directly affects its:
33. In a semiconductor diode, the reverse saturation current is primarily due to:
34. An operational amplifier (op-amp) is an example of a:
35. The 'gain-bandwidth product' of an amplifier is a measure of:
36. In a half-wave rectifier, the output frequency of the ripple is:
37. The characteristic feature of a DIAC is that it:
38. When a p-n junction is reverse biased, the width of the depletion region:
39. The characteristic curve of a JFET in the ohmic region shows that the drain current ($I_D$) is approximately proportional to:
40. A signal generator typically uses a semiconductor device to produce oscillations. Which device is commonly used for this purpose?
41. Which type of amplifier configuration offers high input impedance and low output impedance, making it suitable as a buffer?

More quizzes

• Electrostatics – Electrostatic Potential, Potential Energy and Capacitance▶ Play
• Magnetic Effects of Current and Magnetism▶ Play
• Optics – Wave Optics▶ Play
• Atoms and Nuclei▶ Play
• Current Electricity▶ Play
• Electromagnetic Induction and Alternating Currents▶ Play

Browse all Physics quizzes

More to play