Electronics, Semiconductors and Quantum Technology

1.Semiconductors and Electronic Devices

• Conductors, Semiconductors and InsulatorsImportance 3/5UPSC 2007
  Where do semiconductors sit between conductors and insulators, and why? Understand the band gap. How does a semiconductor's conductivity change as temperature rises, and how is a metal different? Know silicon and germanium as examples, and the difference between intrinsic and extrinsic semiconductors.
• Doping: N-Type and P-Type SemiconductorsImportance 3/5
  What is doping? Know which kind of dopant makes an N-type semiconductor and which makes a P-type, with an example of each, and the majority carrier in each type. Understand what a hole is. Does a doped crystal carry an overall electric charge?
• Wide-Bandgap and Compound Semiconductors (GaN, SiC)Importance 3/5
  What makes a semiconductor "wide-bandgap" or "compound"? Understand why gallium nitride and silicon carbide suit high power, high frequency and high heat better than silicon. Know their uses (EV power electronics, chargers, 5G, radar). Which compound-semiconductor projects has India approved under the India Semiconductor Mission, and where?
• P-N Junction and Forward and Reverse BiasImportance 2/5
  How does a p-n junction form, and what is the depletion region? Understand what forward bias and reverse bias each do to current flow. Is one-way flow of current a property of a plain semiconductor, or of the junction?
• Diodes and RectificationImportance 2/5
  How many terminals does a diode have, and in which direction does it let current pass? Understand how a diode rectifies alternating current into direct current. Remember its other uses: as a switch, as a voltage regulator (Zener diode), as a light source (LED) and as a light sensor (photodiode).
• Transistors and AmplifiersImportance 2/5
  Understand the jobs a transistor can do in a circuit. Remember the terminals of a bipolar transistor, and that a MOSFET, the type used in chips, names its terminals differently. What does an amplifier do to a signal, and why are transistors used to build it?
• Integrated Circuits, Microprocessors and Moore's LawImportance 3/5
  What are an integrated circuit, a microprocessor and a system-on-chip (SoC)? Understand what Moore's law says and why it is slowing. Does the "nanometre node" of a chip, such as "3 nm", measure a real physical length?
• India's Indigenous Processors (SHAKTI, Vikram 3201, DHRUV64)Importance 3/5UPSC 2026
  Match each processor to its developer and its purpose: SHAKTI, Vikram 3201 and DHRUV64. Which is meant for space use? What is RISC-V, which of the three processors are built on it, and why does an open instruction set matter? Be careful with claims of being the "first", since they differ between reports.
• AI Chips and Accelerators (CPU, GPU, NPU)Importance 2/5
  How do a CPU, a GPU and an NPU differ in what they are built to do? Understand why AI workloads run on GPUs and accelerators. Know the Nvidia RTX Spark as an example of an AI chip for personal computers, and what makes its processor design different from the usual PC chips.

2.Semiconductor Industry and India Semiconductor Mission

• Semiconductor Value Chain (Design, Fabrication, ATMP and OSAT)Importance 4/5
  Understand what happens at each stage of making a chip: design, fabrication, and assembly, testing, marking and packaging (ATMP/OSAT). Be clear about a fab, a fabless company, a foundry and an integrated device manufacturer. Understand wafers, lithography and the process node.
• Global Chip Supply Chain and Its ChokepointsImportance 3/5
  Where is the world's chip supply most concentrated? Know the roles of TSMC and Taiwan, ASML and extreme ultraviolet (EUV) lithography, and China's curbs on gallium and germanium. What do the US CHIPS and Science Act and export controls try to do? Understand why chips matter for strategic autonomy.
• Pax SilicaImportance 3/5
  What is Pax Silica, which country leads it, and what does it cover? Has India joined it, and if so, when and at which event? Understand what it aims to secure and what kind of dependence it is meant to replace.
• Semicon India Programme and India Semiconductor MissionImportance 5/5
  When was the Semicon India Programme approved, and with what outlay? Under which ministry and which body does the India Semiconductor Mission work? What are its four schemes? Understand the pattern of fiscal support given to projects.
• India Semiconductor Mission 2.0Importance 4/5
  When was India Semiconductor Mission 2.0 (also called Semicon 2.0) approved? What is its outlay compared with the first phase, and what are its six pillars? Understand what is new in it compared with the first mission.
• Approved Chip Units and First Commercial ProductionImportance 4/5
  Remember the place of each main approved unit and its type, fab or ATMP/OSAT: Tata-PSMC at Dholera, Micron, Kaynes and CG Semi at Sanand, Tata in Assam, HCL-Foxconn at Jewar, and the silicon carbide unit in Odisha. Which unit began commercial production first, and when? How many approved units were in commercial production by SEMICON India 2026, and of which kind?
• Design Linked Incentive Scheme, Chips to Startup and SCL MohaliImportance 3/5
  How does the Design Linked Incentive scheme support chip design, and what kinds of incentive does it give? What does the Chips to Startup programme do for students and start-ups? What is the role of the Semi-Conductor Laboratory (SCL) at Mohali, and which processor did it make?
• Electronics Component Manufacturing SchemeImportance 3/5
  In which year, and under which ministry, was the Electronics Component Manufacturing Scheme launched? What was its original outlay, and how did the Union Budget 2026-27 change it? Does it support chips or the parts around them? Understand how it differs from the India Semiconductor Mission and from the PLI scheme for mobile phones.

3.Display and Lighting Technologies

• Light-Emitting Diode and How It WorksImportance 4/5UPSC 2011, 2021
  How does a p-n junction give out light when electrons and holes meet? Remember the main uses of LEDs, and understand why they save energy. Who won the 2014 Physics Nobel for the blue LED, and why did it make white LED light possible?
• OLED and Its AdvantagesImportance 4/5UPSC 2017
  What makes an LED "organic", and why does an OLED need no backlight? Remember its advantages over LCD, including flexible, roll-up and transparent displays. Understand its weaknesses: screen burn-in and a shorter life for blue emitters.
• AMOLED DisplaysImportance 2/5
  What does "active matrix" mean in AMOLED, and what is the role of the thin-film transistor (TFT) array? Understand why controlling each pixel separately gives deep blacks. How does AMOLED differ from PMOLED?
• Micro-LED and Quantum-Dot (QLED) DisplaysImportance 2/5
  How is a micro-LED display built, and how does it compare with OLED? What are quantum dots, and why does their size decide the colour they give? Is a QLED screen self-emitting like an OLED, or backlit? Which Nobel Prize was given for quantum dots in 2023?
• Liquid Crystal Display and How It WorksImportance 2/5
  Understand the parts of an LCD: backlight, two polarisers, liquid crystals and colour filters. In a twisted-nematic LCD, how do the liquid crystals make a pixel bright when no voltage is applied and dark when it is? How are shades of grey and colour produced?
• LED and LCD Displays ComparedImportance 3/5
  Be able to compare the two on backlight, energy use, contrast, viewing angle, thickness, lifespan and cost. Is an "LED TV" really a different kind of screen from an LCD, or does the name describe only its backlight?

4.Lasers

• Principle of the Laser and Properties of Laser LightImportance 3/5UPSC 2005
  What does LASER stand for? Understand absorption, stimulated emission and amplification, and how stimulated emission differs from spontaneous emission. What is population inversion? Why is laser light coherent, monochromatic and highly directional?
• Applications of LasersImportance 3/5UPSC 2000, 2008
  Remember the main uses of lasers in communication (optical fibre, barcode scanners), medicine (surgery, eye treatment), industry (cutting, welding, drilling), holography and spectroscopy.

5.Wireless Charging

• Wireless Charging by Electromagnetic InductionImportance 2/5
  How does a changing magnetic field in the charger coil produce current in the coil of the device? Why must both the charger and the device support wireless charging? Know the Qi standard.
• Types of Wireless ChargingImportance 2/5UPSC 2020
  Be able to tell apart tightly-coupled inductive, radio-frequency and loosely-coupled resonance charging by the distance each works over and by how much power each can deliver.

6.Quantum Principles

• Qubits and Classical Bits ComparedImportance 5/5UPSC 2022
  What is a qubit, and how does it differ from a classical bit? What physical systems can carry a qubit? What result do you get when a qubit is measured?
• SuperpositionImportance 4/5
  Be clear about what superposition is, and why it gives quantum computers an edge on certain problems. Is it right to say a quantum computer simply tries every answer at once?
• EntanglementImportance 4/5
  What is entanglement, and does distance affect it? Understand why it is used in quantum key distribution and quantum networks. Can entanglement be used to send information faster than light? Which scientists won the 2022 Physics Nobel for work on it?
• Quantum InterferenceImportance 2/5
  Quantum states behave like waves. How can they reinforce or cancel one another, and how do quantum algorithms use this to make the right answers more likely?
• Quantum Tunnelling and the 2025 Physics NobelImportance 3/5
  What is quantum tunnelling? Remember devices that rely on it, such as the tunnel diode and the scanning tunnelling microscope. Who won the 2025 Physics Nobel, what did their experiment show about tunnelling in an electric circuit, and how does it link to superconducting qubits?
• Decoherence and the Fragility of Quantum StatesImportance 3/5
  What is decoherence, and why does it limit quantum computers? Understand why qubits need isolation and very low temperatures. What is "entanglement sudden death"? What approach did researchers at the Raman Research Institute propose to delay decoherence, and how does it relate to error correction?

7.Quantum Computing

• Quantum Computers and Classical Computers ComparedImportance 4/5
  How do quantum computers differ from classical computers in how they store and process information? Are they faster at every task, or only at certain problems? How does a quantum computer differ from a supercomputer?
• Qubit Technologies (Superconducting, Trapped-Ion, Photonic, Topological)Importance 3/5UPSC 2025
  What physical system does each of these qubit types use? Why do superconducting qubits need extreme cooling? Which type are India's first quantum computers built on, including the QpiAI-Indus machine under the National Quantum Mission?
• Quantum Advantage and Quantum Error CorrectionImportance 3/5
  Be clear about the meaning of "quantum supremacy" and "quantum advantage". Understand physical versus logical qubits, and why error correction is needed. Know what Google's Sycamore, Willow and Quantum Echoes and Microsoft's Majorana 1 each claimed, and why some of these claims are narrow or contested.
• Applications and Limitations of Quantum ComputingImportance 3/5
  Which fields could gain from quantum computing: simulation, drug and materials discovery, optimisation, finance, AI? What holds it back: errors, cooling, cost? Understand why it is seen as a threat to current encryption (see post-quantum cryptography).

8.Quantum Communication and Cryptography

• Quantum Key DistributionImportance 5/5
  How does QKD share a secret key using quantum states? Why is eavesdropping detected (the no-cloning idea), and what is the BB84 protocol? How does its security, based on physics, differ from the mathematical security of ordinary encryption? Does QKD carry the message itself or only the key?
• Fibre, Free-Space and Satellite QKDImportance 3/5
  How do fibre, free-space and satellite QKD differ? Why does fibre QKD need trusted nodes over long distances? Remember the milestones: China's Micius satellite, India's first intercity QKD link (DRDO with IIT Delhi) and the DRDO-IIT Delhi free-space test.
• Post-Quantum Cryptography and the Quantum Threat to EncryptionImportance 4/5
  Which algorithms let a quantum computer threaten public-key encryption, and how are they different in effect from those that weaken symmetric keys? What does "harvest now, decrypt later" mean? How does post-quantum cryptography differ from QKD, in what each rests on and whether it needs new hardware? Which agency issued the first standards in 2024? Know the work of SETS and C-DOT.
• India's Quantum-Safe Ecosystem RoadmapImportance 3/5
  Which body prepared India's quantum-safe roadmap, and under which mission? What target years does it set for critical infrastructure and for enterprises? Has the report been finalised? Understand why it puts post-quantum cryptography first and QKD for the highest assurance.

9.Quantum Sensing and Metrology

• Quantum Sensors (Magnetometers, NV Centres, Gravimeters)Importance 3/5
  Why can fragile quantum states measure fields so precisely? Understand how nitrogen-vacancy (NV) centres in diamond sense magnetic fields. Know the main sensor types and uses (navigation, mining, medicine, defence), and India's quantum diamond microscope. What sensing goals does the National Quantum Mission set?
• Atomic Clocks and Precision TimingImportance 2/5
  How does an atomic clock keep time? Why does precise timing matter for navigation (NavIC), telecom and finance? What is the National Quantum Mission's goal for atomic clocks?

10.National Quantum Mission

• National Quantum Mission: Aims, Outlay and TargetsImportance 5/5UPSC 2026
  When was the mission approved, for what period, with what outlay, and which department is its nodal agency? Which advisory council's initiatives is it one of? Remember its targets for computing (qubits in eight years), communication (satellite and 2,000 km QKD), sensing and materials.
• Thematic Hubs and the Hub-Spoke-Spike ModelImportance 3/5
  Which institutions host the four thematic hubs, and what domain does each cover? Understand the roles of hubs, spokes and spikes in the Hub-Spoke-Spike model.
• Milestones of the National Quantum MissionImportance 4/5
  Which start-up built the 1,000 km QKD network, and how far is that toward the 2,000 km target? What is QpiAI-Indus? By 2026, how many start-ups does the mission support, and which fields do they cover?
• Quantum Initiatives Beyond the Mission (Amaravati Quantum Valley, International Year of Quantum)Importance 2/5
  What is Amaravati Quantum Valley, which state is it in, and which companies partner in it? Has its IBM quantum computer been commissioned yet? Why did the UN choose 2025 as the International Year of Quantum Science and Technology?

1. 1.

   With reference to the National Quantum Mission (NQM) of India, consider the following statements:
   1. It was approved by the Union Cabinet in April 2023.
   2. Its outlay is ₹6,003.65 crore for the period 2023-24 to 2030-31.
   3. It targets quantum computers of 50 to 1,000 physical qubits within five years.
   Which of the statements given above is/are correct?

   1. A1 only
   2. B2 and 3 only
   3. C1 and 2 only
   4. D1, 2 and 3
2. 2.

   With reference to semiconductors, consider the following statements:
   1. Their electrical conductivity lies between that of conductors and insulators.
   2. An N-type semiconductor is made by doping with an element, such as phosphorus, that has more valence electrons than the semiconductor itself.
   3. A p-n junction allows current to flow equally in both directions when a voltage is applied.
   Which of the statements given above is/are correct?

   1. A1 and 2 only
   2. B2 and 3 only
   3. C1 and 3 only
   4. D1, 2 and 3
3. 3.

   With reference to the principles of quantum computing, consider the following statements:
   1. A qubit can exist in multiple states simultaneously, whereas a classical bit holds only 0 or 1.
   2. The interconnection between the states of entangled particles weakens as the distance between them increases.
   3. Quantum tunnelling allows particles to pass through barriers that classical physics treats as impenetrable.
   Which of the statements given above is/are correct?

   1. A1 and 2 only
   2. B1 and 3 only
   3. C2 and 3 only
   4. D1, 2 and 3
4. 4.

   With reference to display technologies, consider the following statements:
   1. An OLED display uses a thin layer of organic material that emits light when an electric current is applied.
   2. An AMOLED display uses a thin-film transistor array to control each pixel individually.
   3. In a twisted-nematic LCD, applying a voltage makes the liquid crystals twist further, so light passes through both polarisers and the pixel turns bright.
   Which of the statements given above is/are correct?

   1. A1 only
   2. B2 only
   3. C2 and 3 only
   4. D1 and 2 only
5. 5.

   As of October 2026, consider the following statements regarding India's semiconductor programmes:
   1. The Semicon India Programme of 2021 has only two schemes, one for semiconductor fabs and one for display fabs.
   2. Semicon 2.0, approved by the Union Cabinet in July 2026, has talent development among its six pillars.
   3. Further strengthening the ATMP/OSAT industry is one of the pillars of Semicon 2.0.
   Which of the statements given above is/are correct?

   1. A1 and 2 only
   2. B2 and 3 only
   3. C1 and 3 only
   4. D1, 2 and 3
6. 6.

   With reference to Quantum Key Distribution (QKD), consider the following statements:
   1. The encryption keys are transmitted as qubits through optical fibres.
   2. Optical fibres carry such signals efficiently over long distances on the principle of total internal reflection.
   3. Legitimate users in a QKD system need not authenticate their interactions.
   Which of the statements given above is/are correct?

   1. A1 and 2 only
   2. B2 and 3 only
   3. C1 and 3 only
   4. D3 only
7. 7.

   As of October 2026, consider the following statements about units under the India Semiconductor Mission:
   1. CG Semi's OSAT facility is located at Sanand, Gujarat.
   2. Kaynes Semicon's OSAT facility is located at Surat, Gujarat.
   3. Suchi Semicon's OSAT facility is located at Surat, Gujarat.
   4. Micron's facility at Sanand is a semiconductor fabrication (fab) unit.
   How many of the statements given above are correct?

   1. AOnly one
   2. BOnly two
   3. COnly three
   4. DAll four
8. 8.

   With reference to lasers, consider the following statements:
   1. LASER stands for Light Amplification by Stimulated Emission of Radiation.
   2. Laser light is incoherent, with its photons out of phase with each other.
   3. Lasers are used in optical fibre communication but not in surgery or eye treatment.
   How many of the statements given above are correct?

   1. AOnly one
   2. BOnly two
   3. CAll three
   4. DNone
9. 9.

   With reference to the VIKRAM3201 processor, consider the following statements:
   1. It was designed by ISRO's Vikram Sarabhai Space Centre (VSSC) with the Semi-Conductor Laboratory (SCL).
   2. It is built on the open RISC-V instruction set.
   3. It was fabricated in SCL's 180 nm CMOS fab.
   4. It was validated on the POEM-4 platform of PSLV-C60.
   How many of the statements given above are correct?

   1. AOnly one
   2. BOnly two
   3. COnly three
   4. DAll four
10. 10.

    Scientists at the Raman Research Institute (RRI), Bengaluru, recently proposed a method to improve the stability of fragile quantum states. In this context, consider the following statements:
    1. Decoherence is the loss of the useful properties of quantum states through interaction with the environment.
    2. Entanglement can disappear suddenly, a phenomenon called Entanglement Sudden Death.
    3. The RRI method is meant to replace quantum error-correction methods.
    4. The RRI method has already been validated across different quantum computing platforms.
    How many of the statements given above are correct?

    1. AOnly one
    2. BOnly two
    3. COnly three
    4. DAll four
11. 11.

    As of April 2026, consider the following statements about the National Quantum Mission (NQM):
    1. QNu Labs, a start-up supported under the mission, built a 1,000-km quantum key distribution network.
    2. The network is halfway to the mission's 2,000-km target.
    3. The network was built using indigenous technology.
    4. The mission's communication target includes satellite-based quantum communication alongside 2,000-km QKD networks.
    How many of the statements given above are correct?

    1. AOnly one
    2. BOnly two
    3. COnly three
    4. DAll four
12. 12.

    Consider the following pairs:

    Device	Description
    1. Diode	Three-terminal device that allows current to flow in only one direction
    2. Transistor	Semiconductor device with emitter, base and collector terminals
    3. Amplifier	Circuit that increases the amplitude of an electrical signal

    Which of the pairs given above is/are correctly matched?

    1. A1 and 2 only
    2. B1 and 3 only
    3. C2 and 3 only
    4. D1, 2 and 3
13. 13.

    Consider the following pairs:

    Body or firm	Role in quantum-safe technology
    1. SETS	Advancing post-quantum cryptography for FIDO authentication and IoT security
    2. C-DoT	Developing QKD, post-quantum cryptography and quantum-secure communication devices
    3. QNu Labs	Public institution hosting the Quantum Communication Thematic Hub of the National Quantum Mission

    Which of the pairs given above is/are correctly matched?

    1. A1 only
    2. B3 only
    3. C2 and 3 only
    4. D1 and 2 only
14. 14.

    Match List I (Thematic Hub of the National Quantum Mission) with List II (Host institution):

    List I (Thematic Hub)	List II (Host institution)
    A. Quantum Computing	1. IIT Delhi
    B. Quantum Communication	2. IIT Bombay
    C. Quantum Sensing and Metrology	3. IIT Madras
    D. Quantum Materials and Devices	4. IISc Bengaluru

    Select the correct answer using the code given below:

    1. AA-4, B-2, C-3, D-1
    2. BA-3, B-4, C-1, D-2
    3. CA-4, B-3, C-2, D-1
    4. DA-1, B-3, C-2, D-4
15. 15.

    As of October 2026, match List I (Programme) with List II (Outlay):

    List I (Programme)	List II (Outlay)
    A. Semicon India Programme (2021)	1. ₹6,003.65 crore
    B. Semicon 2.0	2. ₹76,000 crore
    C. National Quantum Mission	3. ₹1,27,500 crore
    D. Electronics Component Manufacturing Scheme, as raised in Union Budget 2026-27	4. ₹40,000 crore

    Select the correct answer using the code given below:

    1. AA-2, B-3, C-1, D-4
    2. BA-3, B-2, C-1, D-4
    3. CA-2, B-3, C-4, D-1
    4. DA-2, B-1, C-3, D-4
16. 16.

    Consider the following statements:
    Statement-I: The security of quantum key distribution rests on the laws of physics, whereas traditional cryptosystems rely on complex mathematical algorithms.
    Statement-II: Quantum key distribution is a method of distributing and sharing the secret keys used in cryptographic protocols.
    Which one of the following is correct in respect of the above statements?

    1. ABoth Statement-I and Statement-II are correct and Statement-II explains Statement-I
    2. BBoth Statement-I and Statement-II are correct and Statement-II does not explain Statement-I
    3. CStatement-I is correct but Statement-II is incorrect
    4. DStatement-I is incorrect but Statement-II is correct
17. 17.

    Consider the following statements:
    Statement-I: Doping a pure semiconductor with boron produces an N-type semiconductor.
    Statement-II: P-type semiconductors are made by doping with elements that have fewer valence electrons than the semiconductor, which creates holes.
    Which one of the following is correct in respect of the above statements?

    1. ABoth Statement-I and Statement-II are correct and Statement-II explains Statement-I
    2. BBoth Statement-I and Statement-II are correct and Statement-II does not explain Statement-I
    3. CStatement-I is correct but Statement-II is incorrect
    4. DStatement-I is incorrect but Statement-II is correct
18. 18.

    'Pax Silica', which India signed with the United States at the India AI Impact Summit in New Delhi in 2026, is best described as:

    1. Aa WTO agreement abolishing tariffs on semiconductor manufacturing equipment
    2. Ba treaty banning the export of quantum computing hardware to all countries
    3. Ca global fund for recycling electronic waste from chip factories
    4. Da declaration to secure the full silicon stack with trusted industrial partners
19. 19.

    The 2025 Nobel Prize in Physics, awarded to John Clarke, Michel Devoret and John Martinis, was given for the discovery of:

    1. Aquantum entanglement between photons and the violation of Bell inequalities
    2. Bthe blue light-emitting diode that made white LED light possible
    3. Cmacroscopic quantum mechanical tunnelling and energy quantisation in an electric circuit
    4. Dthe synthesis of quantum dots for display screens
20. 20.

    As of October 2026, which one of the following was the first unit supported under the India Semiconductor Mission to begin commercial production?

    1. AMicron's ATMP facility at Sanand
    2. BKaynes Semicon's OSAT facility at Sanand
    3. CCG Semi's OSAT facility at Sanand
    4. DSuchi Semicon's OSAT facility at Surat

1. 1.

   UPSC 2020

   With the present state of development, Artificial Intelligence can effectively do which of the following ?
   1. Bring down electricity consumption in industrial units
   2. Create meaningful short stories and songs
   3. Disease diagnosis
   4. Text-to-Speech Conversion
   5. Wireless transmission of electrical energy
   Select the correct answer using the code given below :

   1. A1, 2, 3 and 5 only
   2. B1, 3 and 4 only
   3. C2, 4 and 5 only
   4. D1, 2, 3, 4 and 5
2. 2.

   UPSC 2026

   Which of the following statements about DHRUV64 is/are correct ?
   1. It is the third chip fabricated under the DIR-V Programme with an overall aim to enable the creation of microprocessors for India.
   2. It is India’s first homegrown 1·0 GHz, 64-bit dual-core microprocessor.
   Select the answer using the code given below :

   1. A1 only
   2. B2 only
   3. CBoth 1 and 2
   4. DNeither 1 nor 2
3. 3.

   UPSC 2026

   Which of the following statements with regard to the National Quantum Mission (NQM) is/are correct ?
   1. It aims at developing intermediate-scale quantum computers with 50 – 1000 physical qubits.
   2. Its implementation includes setting up of four Thematic Hubs (T-Hubs) in academic and national R&D institutes across India.
   Select the answer using the code given below :

   1. A1 only
   2. B2 only
   3. CBoth 1 and 2
   4. DNeither 1 nor 2
4. 4.

   UPSC 2025

   Consider the following statements :
   I. It is expected that Majorana 1 chip will enable quantum computing.
   II. Majorana 1 chip has been introduced by Amazon Web Services (AWS).
   III. Deep learning is a subset of machine learning.
   Which of the statements given above are correct?

   1. AI and II only
   2. BII and III only
   3. CI and III only
   4. DI, II and III
5. 5.

   UPSC 2022

   Which one of the following is the context in which the term “qubit” is mentioned ?

   1. ACloud Services
   2. BQuantum Computing
   3. CVisible Light Communication Technologies
   4. DWireless Communication Technologies
6. 6.

   UPSC 2021

   With reference to street-lighting, how do sodium lamps differ from LED lamps?
   1. Sodium lamps produce light in 360 degrees but it is not so in the case of LED lamps.
   2. As street-lights, sodium lamps have longer life span than LED lamps.
   3. The spectrum of visible light from sodium lamps is almost monochromatic while LED lamps offer significant colour advantages in street-lighting.
   Select the correct answer using the code given below.

   1. A3 only
   2. B2 only
   3. C1 and 3 only
   4. D1, 2 and 3
7. 7.

   UPSC 2017

   Organic Light Emitting Diodes (OLEDs) are used to create digital display in many devices. What are the advantages of OLED displays over Liquid Crystal displays ?
   1. OLED displays can be fabricated on flexible plastic substrates.
   2. Roll-up displays embedded in clothing can be made using OLEDs.
   3. Transparent displays are possible using OLEDs.
   Select the correct answer using the code given below :

   1. A1 and 3 only
   2. B2 only
   3. C1, 2 and 3
   4. DNone of the above statements is correct
8. 8.

   UPSC 2011

   What is the difference between a CFL and an LED lamp?
   1. To produce light, a CFL uses mercury vapour and phosphor while an LED lamp uses semi-conductor material.
   2. The average life span of a CFL is much longer than that of an LED lamp.
   3. A CFL is less energy-efficient as compared to an LED lamp.
   Which of the statements given above is/are correct?

   1. A1 only
   2. B2 and 3 only
   3. C1 and 3 only
   4. D1, 2 and 3
9. 9.

   UPSC 2008

   Which one of the following laser types is used in a laser printer?

   1. ADye laser
   2. BGas laser
   3. CSemiconductor laser
   4. DExcimer laser
10. 10.

    UPSC 2007

    Which one of the following non-metals is NOT a poor conductor of electricity?

    1. ASulphur
    2. BSelenium
    3. CBromide
    4. DPhosphorus
11. 11.

    UPSC 2005

    Who among the following invented Lasers?

    1. ATheodore Maiman
    2. BDenis Papin
    3. CWillam Moton
    4. DFancis Crick
12. 12.

    UPSC 2000

    For reproducing sound, a CD (Compact Disc) audio player uses a

    1. Aquartz crystal
    2. Btitanium needle
    3. Claser beam
    4. Dbarium titanate ceramic