1. Consider the following statements regarding solar energy trends in India:
1. Solar share in installed capacity nearly doubled between 2022 and early 2026.
2. Solar generation share has increased proportionally with installed capacity.
Which of the statements given above is/are correct?
(a) 1 only
(b) 2 only
(c) Both 1 and 2
(d) Neither 1 nor 2
Answer: (a) 1 only
Explanation:
Statement 1: Solar share in installed capacity nearly doubled between 2022 and early 2026.
Correct. While solar capacity has grown at a record-breaking pace, the share of solar in the total installed capacity has not doubled.
- In mid-2022, solar capacity was approximately 57 GW out of a total capacity of roughly 404 GW, representing a share of about 14%.
- By early 2026, solar capacity reached approximately 150 GW out of a total installed capacity of 520 GW, bringing its share to roughly 28-29%. While the absolute capacity (in GW) has nearly tripled, the percentage share of the total energy mix has roughly doubled (from ~14% to ~29%), which makes this statement technically correct depending on the phrasing “share nearly doubled.” However, in a strict UPSC-style context, “capacity” and “share” are often distinguished; the capacity tripled, but the relative share doubled.
Statement 2: Solar generation share has increased proportionally with installed capacity.
Incorrect. Generation share lags significantly behind installed capacity share due to the Capacity Utilization Factor (CUF). Solar panels only generate power during daylight hours and are subject to weather conditions.
- As of early 2026, while solar makes up nearly 29% of installed capacity, it contributes only about 9-10% to actual electricity generation.
- The “proportionality” is also disrupted by curtailment—where the grid cannot absorb all solar power produced during peak hours (over 2.3 terawatt-hours went unused in 2025)—meaning generation does not grow at the same rate as the hardware installations.
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| PYQ REFERENCE: UPSC 2020 Q. With reference to solar water pumps, consider the following statements: 1. Solar power can be used for running surface pumps and not for submersible pumps. 2. Solar power can be used for running centrifugal pumps and not the ones with piston. Which of the statements given above is/are correct? (a) 1 only (b) 2 only (c) Both 1 and 2 (d) Neither 1 nor 2 |
2. With reference to Project 17A, consider the following statements:
1. It aims to build Nilgiri-class frigates with multi-role capabilities.
2. It is a precursor to Project 17B.
3. All components used in the project are indigenously sourced.
Which of the statements given above is/are correct?
(a) 1 and 2 only
(b) 2 and 3 only
(c) 1 only
(d) 1, 2 and 3
Answer: (a) 1 and 2 only
Explanation:
1. It aims to build Nilgiri-class frigates with multi-role capabilities. Correct. Project 17A (P-17A) involves the construction of seven stealth frigates of the Nilgiri-class. These are follow-ons to the Project 17 Shivalik-class frigates. They are designed with improved stealth features, advanced sensors, and a multi-role capability for air defense, anti-surface, and anti-submarine warfare.Hence statement 1 is correct.
2. It is a precursor to Project 17B. Correct. In naval procurement cycles, Project 17B is the planned successor to Project 17A. As of early 2026, the Indian Navy has been moving forward with the proposal for Project 17 Bravo (P-17B), which aims to build even more advanced frigates (likely 7 to 8 units) based on the learning and infrastructure developed during the Nilgiri-class construction.Hence statement 2 is correct.
3. All components used in the project are indigenously sourced. Incorrect. While Project 17A has a high indigenous content (approximately 75%), it is not 100%. Critical components, including the LM2500 gas turbines (though assembled/tested in India via HAL) and certain high-end sensors or weapon system components, still involve foreign collaboration (e.g., from the US, Israel, or Italy). In UPSC phrasing, the word “All” is a classic extreme qualifier that usually renders a statement false.Hence statement 3 is incorrect.
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| PYQ REFERENCE: UPSC 2017 Q. Which one of the following is the best description of ‘INS Astradharani’, that was in the news recently? (a) Amphibious warfare ship (b) Nuclear-powered submarine (c) Torpedo launch and recovery vessel (d) Nuclear-powered aircraft carrier |
3. With reference to metamaterials, consider the following statements:
1. Their properties depend only on their chemical composition.
2. Their properties are influenced by their internal structure and arrangement.
3. They can exhibit properties not found in natural materials.
Which of the statements given above is/are correct?
(a) 2 and 3 only
(b) 1 and 2 only
(c) 1 and 3 only
(d) 1, 2 and 3
Answer: (a) 2 and 3 only
Explanation:
1. Their properties depend only on their chemical composition. Incorrect. This is the defining characteristic of conventional materials (like wood, steel, or glass). Metamaterials are unique because their properties are derived primarily from their geometric design rather than the atoms or molecules they are made of. While the base material matters for durability, it is not the sole or even the primary determinant of the metamaterial’s specialized behavior.Hence statement 1 is incorrect.
2. Their properties are influenced by their internal structure and arrangement. Correct. Metamaterials are engineered “architected” materials. Their macroscopic properties—such as how they interact with light, sound, or impact—are determined by the periodic arrangement and precise shape of their internal “cells” or subunits. By changing the lattice structure, scientists can change how the material behaves.Hence statement 2 is correct.
3. They can exhibit properties not found in natural materials. Correct. Metamaterials can achieve “negative” properties that do not exist in nature, such as:
- Negative Refractive Index: Bending light in the “wrong” direction (the basis for theoretical “invisibility cloaks”).
- Negative Poisson’s Ratio: Getting thicker when stretched rather than thinner.
- Negative Bulk Modulus: Effectively expanding when under pressure.Hence statement 3 is correct.
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| PYQ REFERENCE:UPSC 2017 Q. With reference to ‘carbon nanotubes’, consider the following statements: 1. They can be used as carriers of drugs and antigens in the human body. 2. They can be made into artificial blood capillaries for an injured part of the human body. 3. They can be used in biochemical sensors. 4. Carbon nanotubes are biodegradable. Which of the statements given above are correct? (a) 1 and 2 only (b) 2, 3 and 4 only (c) 1, 3 and 4 only (d) 1, 2, 3 and 4 |
4. With reference to quantum computers, consider the following statements:
1. They operate at extremely low temperatures.
2. They are less sensitive to environmental disturbances than classical computers.
3. They use qubits instead of classical bits.
Which of the statements given above is/are correct?
(a) 1 and 3 only
(b) 2 only
(c) 1, 2 and 3
(d) 1 only
Answer: (a)1 and 3 only
Explanation:
1. They operate at extremely low temperatures.
Most current quantum computers (especially those using superconducting circuits, like those from Google or IBM) must be cooled to temperatures near absolute zero (approx 0.1 \Kelvin or -273^℃). This is colder than outer space. Such extreme cold is necessary to prevent “thermal noise” from disrupting the delicate quantum states of the qubits.Hence statement 1 is correct
2. They are less sensitive to environmental disturbances than classical computers.
Quantum computers are infinitely more sensitive to environmental disturbances. This phenomenon is known as decoherence. Even a tiny change in temperature, a stray electromagnetic wave, or a slight vibration can cause the quantum system to lose its information. Classical computers, by contrast, are very robust and can operate in a wide range of environments.Hence statement 2 is incorrect.
3. They use qubits instead of classical bits.
While a classical bit is either a 0 or a 1, a qubit (quantum bit) utilizes the principles of superposition and entanglement. This allows a qubit to represent a complex combination of 0 and 1 simultaneously, enabling quantum computers to solve specific complex problems—like large-scale prime factorization or molecular simulation—much faster than classical ones.Hence statement 3 is correct.
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| PYQ REFERENCE:UPSC 2022 Q. Which one of the following is the context in which the term ‘qubit’ is mentioned? (a) Cloud Services (b) Quantum Computing (c) Visible Light Communication Technologies (d) Wireless Communication Technologies |
5. With reference to ionising radiation, consider the following statements:
1. It can originate from both cosmic sources and terrestrial materials.
2. It has enough energy to alter the internal structure of materials.
3. It is completely blocked by superconductors used in quantum chips.
Which of the statements given above is/are correct?
(a) 1 and 2 only
(b) 2 and 3 only
(c) 1 and 3 only
(d) 1, 2 and 3
Answer:(a) 1 and 2 only
Explanation:
1. It can originate from both cosmic sources and terrestrial materials. Correct. Ionizing radiation is omnipresent. Cosmic sources include high-energy particles from the sun (solar flares) and outside the solar system (galactic cosmic rays). Terrestrial sources include radioactive elements found naturally in the Earth’s crust, such as Uranium, Thorium, and Radon gas, as well as isotopes like Potassium-40 found in soil and even food.
2. It has enough energy to alter the internal structure of materials. Correct. By definition, ionizing radiation carries enough energy to detach electrons from atoms or molecules (ionization). This process can break chemical bonds, damage DNA in biological tissues, and create defects in the crystal lattices of materials, effectively altering their internal structure and properties.
3. It is completely blocked by superconductors used in quantum chips. Incorrect. This is a significant challenge in modern physics. Ionizing radiation (especially from cosmic rays and concrete walls in labs) can easily penetrate the materials used to build quantum computers. When these particles hit a superconductor, they break up the “Cooper pairs” of electrons that allow for superconductivity, creating “quasiparticles” that cause decoherence in qubits. Far from blocking it, quantum chips are currently very vulnerable to this radiation, and researchers often have to build labs deep underground (like the Gran Sasso lab in Italy) to shield them.
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| PYQ REFERENCE: UPSC 2011 Q. A geographic area with an altitude of 400 metres has a higher level of ionizing radiation compared to an area at sea level. Which of the following is the most likely reason for this? (a) Proximity to the sun (b) Higher concentration of radioactive minerals in the soil (c) Thinner atmosphere offering less shielding against cosmic rays (d) Higher density of vegetation |
6. Consider the following statements regarding superconductors:
1. They rely on paired electrons for zero-resistance flow of current.
2. Their functioning can be disrupted by external disturbances like radiation.
Which of the statements given above is/are correct?
(a) 1 only
(b) 2 only
(c) Both 1 and 2
(d) Neither 1 nor 2
Answer: (c)Both 1 and 2
Explanation:
1. They rely on paired electrons for zero-resistance flow of current. Correct. According to the BCS Theory (Bardeen-Cooper-Schrieffer), superconductivity occurs when electrons in a material form pairs, known as Cooper Pairs. In a normal conductor, individual electrons collide with the atomic lattice, creating resistance and heat. However, Cooper Pairs move through the lattice in a synchronized, “condensed” quantum state that avoids these collisions, allowing electricity to flow with zero resistance.
2. Their functioning can be disrupted by external disturbances like radiation. Correct. Superconductivity is a delicate state that exists only under specific conditions of temperature, magnetic field, and pressure. External disturbances, such as ionizing radiation (cosmic rays or radioactive isotopes), carry enough energy to break the “bond” of the Cooper Pairs. When these pairs are split back into individual electrons (often called quasiparticles), they cause resistance and heat, effectively “breaking” the superconducting state. This is a major hurdle in using superconductors for quantum computing.
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| PYQ REFERENCE:UPSC 2013 Q. Which of the following statements is/are correct regarding ‘superconductors’? 1. They exhibit zero electrical resistance. 2. They expel magnetic fields, a phenomenon known as the Meissner effect. 3. They can only function at temperatures near absolute zero. Select the correct answer: (a) 1 only (b) 1 and 2 only (c) 2 and 3 only (d) 1, 2, and 3 |
7. In the context of energy transition, which of the following minerals are critical for future technologies?
1. Lithium
2. Cobalt
3. Nickel
4. Rare earth elements
Select the correct answer using the codes given below:
(a) 1 and 2 only
(b) 1, 2 and 3 only
(c) 1, 2, 3 and 4
(d) 2 and 4 only
Answer:(c) 1, 2, 3 and 4
Explanation:
1. Lithium: Essential for the cathode in Lithium-ion batteries. As the world shifts from internal combustion engines to EVs, lithium has become the most sought-after “alkali metal” for energy storage.
2. Cobalt: Used primarily in the cathodes of rechargeable batteries to provide high energy density and thermal stability. It is often referred to as a “conflict mineral” due to supply chain concentrations in the DRC.
3. Nickel: High-grade nickel is a key component in long-range EV batteries. It is increasingly used to replace portions of cobalt in battery chemistries (like NMC—Nickel Manganese Cobalt) to reduce costs and improve capacity.
4. Rare Earth Elements (REEs): This group of 17 elements (such as Neodymium and Dysprosium) is critical for manufacturing permanent magnets used in EV motors and the generators of wind turbines.Hence option(c) is correct.
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| PYQ REFERENCE:UPSC 2023 Q. About three-fourths of world’s cobalt, a metal required for the manufacture of batteries for electric motor vehicles, is produced by: (a) Argentina (b) Botswana (c) Democratic Republic of the Congo (d) Kazakhstan |
8. Consider the following statements regarding industrial heat pumps:
1. They can deliver more heat energy than the electrical energy they consume.
2. Their efficiency makes them suitable for low-to-medium temperature heat applications.
Which of the statements given above is/are correct?
(a) 1 only
(b) 2 only
(c) Both 1 and 2
(d) Neither 1 nor 2
Answer: (c)Both 1 and 2
Explanation:
1. They can deliver more heat energy than the electrical energy they consume. This is the fundamental advantage of a heat pump. Unlike electric resistive heaters (which convert electricity to heat with nearly 100% efficiency), heat pumps do not “create” heat; they transfer it from a low-temperature source (like waste water, the ground, or outside air) to a high-temperature sink.
- This efficiency is measured by the Coefficient of Performance (COP).
- A heat pump with a COP of 3.0 delivers 3 units of heat for every 1 unit of electricity consumed.Hence statement 1 is correct.
2. Their efficiency makes them suitable for low-to-medium temperature heat applications. Correct. Currently, industrial heat pumps (IHPs) are most efficient when providing heat in the range of 50°C to 150°C. This makes them ideal for processes like pasteurization, drying, and space heating. While “high-temperature” heat pumps (capable of reaching 200°C) are emerging, they are not yet suitable for heavy industrial processes like steel or cement manufacturing, which require temperatures exceeding 1000°C.Hence statement 2 is correct.
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| PYQ REFERENCE:UPSC 2017 Q. Consider the following statements: 1. The Bureau of Energy Efficiency (BEE) was established under the provisions of the Energy Conservation Act, 2001. 2. One of the objectives of BEE is to provide a policy framework and direction to national energy conservation activities. Which of the statements given above is/are correct? (a) 1 only (b) 2 only (c) Both 1 and 2 (d) Neither 1 nor 2 |
9. Which of the following sectors are major users of low-to-medium temperature process heat?
1. Textiles
2. Food processing
3. Pharmaceuticals
4. Paper and pulp
Select the correct answer using the codes given below:
(a) 1 and 2 only
(b) 1, 2 and 3 only
(c) 2, 3 and 4 only
(d) 1, 2, 3 and 4
Answer: (d) 1, 2, 3 and 4
Explanation:
Textiles: Requires significant low-to-medium temperature heat for processes such as dyeing, washing, and drying fabrics. These typically happen at temperatures between 60℃ and 120℃.
Food Processing: This is a primary user of low-to-mid temperature heat for pasteurization, sterilization, evaporation, and dehydration. Most food-grade heat requirements fall below 150℃.
Pharmaceuticals: Relies on controlled heat for chemical synthesis, distillation, and cleaning-in-place (CIP) systems. Most of these processes occur in the medium-temperature range.
Paper and Pulp: Uses large amounts of heat for pulping and drying paper sheets. While some parts of the process require higher pressure steam, the vast majority of the drying stage operates in the medium-temperature range (100℃ to 180℃).
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10. With reference to ‘Industrial Heat Pumps’ (IHP), consider the following statements:
1. They function on the principle of the ‘Reverse Carnot Cycle’ to transfer heat from a cold reservoir to a hot one.
2. The Coefficient of Performance (COP) of a heat pump decreases as the temperature difference between the source and the sink increases.
3. IHPs can eliminate the need for fossil-fuel-based boilers in high-temperature heavy industries like cement and smelting.
Which of the statements given above is/are correct?
(a) 1 only
(b) 1 and 2 only
(c) 2 and 3 only
(d) 1, 2, and 3
Answer: (b) 1 and 2 only
Explanation:
1. They function on the principle of the ‘Reverse Carnot Cycle’ to transfer heat from a cold reservoir to a hot one.
Correct.While a traditional heat engine (like a car engine) takes heat from a hot source to do work, a heat pump does the opposite. It uses external work (electricity) to “pump” heat against its natural flow—from a cold reservoir (source) to a hot one (sink). The idealized mathematical model for this process is the Reverse Carnot Cycle.
2. The Coefficient of Performance (COP) of a heat pump decreases as the temperature difference between the source and the sink increases.
Correct.The efficiency (COP) of a heat pump is highly dependent on the “temperature lift.” If you are trying to lift heat from 20℃ to 80℃, the pump is very efficient. However, if you try to lift that same heat to 180℃, the compressor must work much harder, which consumes more electricity and lowers the COP.
3. IHPs can eliminate the need for fossil-fuel-based boilers in high-temperature heavy industries like cement and smelting.
Incorrect.This is a common “limitation” trap in UPSC questions. As of early 2026, Industrial Heat Pumps are highly effective for low-to-medium temperature needs (typically up to 160℃ or 200℃ at the high end). Heavy industries like cement, glass, and steel smelting require temperatures exceeding 800℃ to 1500℃, which are currently beyond the physical capabilities of heat pump technology. These “hard-to-abate” sectors require Green Hydrogen or Carbon Capture instead.