Ready to test your knowledge with a TNPSC Physics Energy Test? This quiz includes important TNPSC Physics Energy MCQs designed for TNPSC aspirants. Covering key General Science concepts, this quiz includes questions on renewable and non-renewable energy sources, solar energy, wind energy, hydroelectric energy, biomass, geothermal energy, nuclear energy, and energy transformations. Designed in the TNPSC exam pattern, these MCQs will help you strengthen your understanding of important Physics Energy concepts and improve your exam readiness.
Detailed Explanation For All Questions – TNPSC Physics Energy Test 3
This section contains detailed explanations for every question in the TNPSC Physics Energy Test. It explains the concepts of Topics renewable and non-renewable energy sources, solar energy, wind energy, hydroelectric energy, biomass, geothermal energy, nuclear energy, and energy transformations to strengthen your understanding of TNPSC Physics Energy topics covered in the General Science syllabus. These explanations will help you improve your TNPSC Physics knowledge and prepare more confidently for the TNPSC examination.
1. Which of the following is a renewable source of energy?
Answer: C. Solar energy
Solar energy is a renewable source because it is continuously supplied by the Sun and is naturally replenished. Unlike fossil fuels such as coal, petroleum, and natural gas, solar energy does not get exhausted with use. It is also an environmentally friendly source of energy, producing electricity without releasing harmful greenhouse gases. Due to its abundance and sustainability, solar energy plays an important role in reducing dependence on non-renewable energy resources.
Quick Revision
- Renewable energy is naturally replenished.
- Solar energy is one of the most widely used renewable energy sources.
- It produces clean energy with minimal environmental pollution.
Real-Life Example
Solar panels installed on rooftops convert sunlight into electricity to power homes, schools, and offices.
2. Which energy source is obtained from plant and animal waste?
Answer: A. Biomass
Biomass energy is produced from organic materials such as agricultural residues, wood, crop waste, food waste, and animal dung. These materials store chemical energy through photosynthesis, which can be converted into heat, electricity, or biogas. Biomass is considered a renewable energy source because new plants and organic materials can be grown or produced continuously. It also helps reduce waste by converting biodegradable materials into useful energy.
Quick Revision
- Biomass is obtained from plant and animal waste.
- It is a renewable source of energy.
- Biomass can produce heat, electricity, and biogas.
Real-Life Example
Biogas plants in rural areas use cattle dung and kitchen waste to produce cooking gas for households.
3. Which of the following is a non-renewable source of energy?
Answer: B. Coal
Coal is a non-renewable energy source because it is formed from ancient plant remains buried deep inside the Earth over millions of years. Since the rate of formation is extremely slow, coal cannot be replaced within a human lifetime. Burning coal releases carbon dioxide, sulphur dioxide, and other pollutants, contributing to air pollution and climate change. Although it is an important source of electricity, its limited availability makes conservation necessary.
Quick Revision
- Coal is a fossil fuel.
- It takes millions of years to form.
- Burning coal causes environmental pollution.
Real-Life Example
Many thermal power stations generate electricity by burning coal to produce steam that drives turbines.
4. Wind energy is ultimately derived from:
Answer: B. Solar energy
Wind energy originates from solar energy because the Sun heats the Earth’s surface unevenly. Different regions warm at different rates, creating temperature and pressure differences in the atmosphere. Air moves from high-pressure areas to low-pressure areas, producing wind. Wind turbines capture this moving air and convert its mechanical energy into electrical energy. Therefore, wind energy is considered an indirect form of solar energy.
Quick Revision
- Wind is created by uneven heating of the Earth by the Sun.
- Wind energy is an indirect form of solar energy.
- Wind turbines convert wind energy into electricity.
Real-Life Example
Large wind farms in Tamil Nadu generate electricity using strong seasonal winds.
5. Hydroelectric power stations mainly convert:
Answer: C. Mechanical → Electrical
In a hydroelectric power station, water stored behind a dam flows through pipes at high speed and rotates turbines. The moving water possesses mechanical energy, which turns the turbine connected to a generator. The generator then converts this mechanical energy into electrical energy using electromagnetic induction. Hydroelectric power is a renewable source of electricity because it depends on the natural water cycle.
Quick Revision
- Flowing water rotates turbines.
- Turbines drive generators to produce electricity.
- Energy conversion: Mechanical Energy → Electrical Energy.
Real-Life Example
The Mettur Dam Hydroelectric Power Station in Tamil Nadu generates electricity using the energy of flowing water.
6. Which of the following produces the least air pollution during electricity generation?
Answer: C. Solar
Solar energy generates electricity by converting sunlight directly into electrical energy using photovoltaic (PV) cells. Since no fuel is burned during this process, solar power does not release smoke, carbon dioxide, sulphur dioxide, or other harmful air pollutants. This makes it one of the cleanest and most environmentally friendly sources of electricity. Although manufacturing solar panels has some environmental impact, electricity generation itself is virtually pollution-free.
Quick Revision
- Solar power does not require fuel combustion.
- It produces electricity with minimal air pollution.
- Solar energy is a clean and renewable energy source.
Real-Life Example
Solar parks across India generate electricity during the daytime without emitting harmful gases into the atmosphere.
7. Geothermal energy is obtained from:
Answer: B. Earth’s interior
Geothermal energy is obtained from the natural heat stored inside the Earth’s crust. This heat originates mainly from the Earth’s formation and the radioactive decay of minerals deep underground. In geothermal power plants, hot water or steam from underground reservoirs is used to rotate turbines connected to generators, producing electricity. Since the Earth’s internal heat is continuously available, geothermal energy is considered a renewable source.
Quick Revision
- Geothermal energy comes from the Earth’s internal heat.
- Underground steam or hot water is used to generate electricity.
- It is a renewable and reliable energy source.
Real-Life Example
Countries like Iceland use geothermal power extensively for electricity generation and home heating due to their volcanic activity.
8. Which of the following is the major advantage of renewable energy sources?
Answer: C. Continuous replenishment
The greatest advantage of renewable energy sources is that they are naturally replenished through processes such as sunlight, wind, rainfall, and plant growth. Unlike fossil fuels, they do not get exhausted with regular use. Renewable energy also helps reduce dependence on limited natural resources and contributes to a cleaner environment by lowering greenhouse gas emissions.
Quick Revision
- Renewable resources are naturally replenished.
- They can be used repeatedly without depletion.
- They support sustainable energy production.
Real-Life Example
Wind turbines continue to generate electricity whenever sufficient wind is available, making wind energy a sustainable resource.
9. Nuclear power plants generate heat mainly through:
Answer: C. Nuclear fission
Nuclear power plants produce heat through the process of nuclear fission, in which the nucleus of a heavy atom such as uranium-235 splits into smaller nuclei. This reaction releases a tremendous amount of heat energy, which is used to convert water into steam. The steam rotates turbines connected to generators, producing electricity. Nuclear fission provides a large amount of energy from a relatively small quantity of fuel.
Quick Revision
- Nuclear fission is the splitting of heavy atomic nuclei.
- It releases a large amount of heat energy.
- The heat is used to generate electricity through steam turbines.
Real-Life Example
The Kudankulam Nuclear Power Plant in Tamil Nadu generates electricity using controlled nuclear fission.
10. Which sequence correctly represents the energy conversion in a solar-powered calculator?
Answer: A. Light → Electrical
A solar-powered calculator contains photovoltaic (solar) cells that absorb sunlight and convert light energy directly into electrical energy. The electricity produced powers the calculator without the need for disposable batteries under sufficient lighting conditions. This direct conversion of sunlight into electricity is known as the photovoltaic effect.
Quick Revision
- Solar cells convert light energy into electrical energy.
- This process is called the photovoltaic effect.
- Solar-powered devices operate using renewable energy.
Real-Life Example
Solar-powered calculators commonly used by students and shopkeepers operate efficiently under sunlight or bright indoor lighting.
11. Which of the following is an example of energy transformation in a wind turbine?
Answer: B. Mechanical → Electrical
A wind turbine converts the kinetic energy of moving air into mechanical energy by rotating its blades. The rotating blades drive a shaft connected to a generator, which converts the mechanical energy into electrical energy through electromagnetic induction. Wind energy is renewable, environmentally friendly, and plays an important role in reducing dependence on fossil fuels for electricity generation.
Quick Revision
- Wind turbines use the kinetic energy of moving air.
- Mechanical energy is converted into electrical energy.
- Wind energy is a clean and renewable source of electricity.
Real-Life Example
The Muppandal Wind Farm in Tamil Nadu generates electricity by converting the mechanical energy of wind into electrical energy.
12. Which renewable energy source is most suitable in regions with abundant hot springs?
Answer: C. Geothermal
Geothermal energy is generated by utilizing the natural heat stored beneath the Earth’s surface. Areas with hot springs, geysers, or volcanic activity have underground reservoirs of hot water and steam that can be used to produce electricity or provide direct heating. Since the Earth’s internal heat is continuously available, geothermal energy is considered a reliable renewable energy source.
Quick Revision
- Geothermal energy comes from the Earth’s internal heat.
- Hot springs indicate geothermal energy potential.
- It is a renewable and dependable source of energy.
Real-Life Example
Iceland generates a significant portion of its electricity and heating needs using geothermal energy from underground hot water reservoirs.
13. Which of the following is a fossil fuel?
Answer: A. Coal
Coal is a fossil fuel formed from the remains of ancient plants that were buried under layers of soil and rock millions of years ago. Over time, heat and pressure transformed this organic matter into coal. Since coal takes millions of years to form, it cannot be replaced within a short period, making it a non-renewable energy resource. Burning coal also releases pollutants that contribute to environmental pollution.
Quick Revision
- Coal is a fossil fuel.
- It is formed from ancient plant remains.
- Coal is a non-renewable source of energy.
Real-Life Example
Coal is widely used in thermal power plants to generate electricity by producing steam that drives turbines.
14. Which energy source is directly affected by the speed of moving air?
Answer: C. Wind
Wind energy depends directly on the speed of moving air because the amount of electricity generated by a wind turbine increases as wind speed increases, up to the turbine’s safe operating limit. If the wind is too weak, electricity generation decreases, while excessively strong winds may require turbines to shut down for safety. Therefore, locations with consistent wind speeds are ideal for wind power generation.
Quick Revision
- Wind turbines require moving air to generate electricity.
- Higher wind speeds generally produce more electrical power.
- Suitable locations are essential for efficient wind energy production.
Real-Life Example
Coastal regions and mountain passes are preferred locations for wind farms because they receive strong and consistent winds.
15. Which of the following is the primary purpose of a dam in a hydroelectric power station?
Answer: B. Store water
A dam stores a large quantity of water at a higher level, creating gravitational potential energy. When water is released, it flows through penstocks at high speed and rotates turbines connected to generators. This process converts the energy of flowing water into electrical energy. The stored water also helps maintain a steady supply of electricity throughout the year.
Quick Revision
- Dams store water at a higher elevation.
- Stored water provides the energy needed to rotate turbines.
- Hydroelectric power is a renewable source of electricity.
Real-Life Example
The Mettur Dam in Tamil Nadu stores water that is used for hydroelectric power generation as well as irrigation.
16. Which of the following is an advantage of nuclear energy?
Answer: C. Large energy production
Nuclear energy is capable of producing an enormous amount of electricity from a very small quantity of nuclear fuel, such as uranium. During nuclear fission, the nucleus of a heavy atom splits into smaller nuclei, releasing a tremendous amount of heat. This heat is used to produce steam, which drives turbines connected to generators. Compared to fossil fuels, nuclear power plants generate large amounts of electricity with relatively low greenhouse gas emissions during operation.
Quick Revision
- Nuclear energy produces a large amount of electricity from a small amount of fuel.
- Heat is generated through nuclear fission.
- It has high energy output with low carbon emissions during operation.
Real-Life Example
The Kudankulam Nuclear Power Plant in Tamil Nadu supplies a significant amount of electricity to the national power grid using nuclear energy.
17. Which of the following is a limitation of solar energy?
Answer: B. Depends on sunlight
Solar energy depends on the availability of sunlight to generate electricity. Solar panels produce maximum power during bright, sunny conditions, while electricity generation decreases on cloudy days and stops at night. To ensure a continuous power supply, solar systems often require battery storage or support from the electrical grid. Despite this limitation, solar energy remains one of the cleanest and most sustainable renewable energy sources.
Quick Revision
- Solar energy requires sunlight to generate electricity.
- Power generation decreases during cloudy weather and at night.
- Battery storage can help overcome this limitation.
Real-Life Example
Many homes with rooftop solar panels use batteries to store excess electricity generated during the day for use after sunset.
18. Which energy conversion takes place in a biogas stove?
Answer: A. Chemical → Heat
Biogas is a renewable fuel produced by the decomposition of organic waste such as animal dung, food waste, and agricultural residues. When biogas burns in a stove, the chemical energy stored in the fuel is converted into heat energy. This heat is then used for cooking and other domestic purposes. Biogas is an eco-friendly alternative to conventional fossil fuels because it utilizes biodegradable waste and reduces environmental pollution.
Quick Revision
- Biogas stores chemical energy.
- Burning biogas converts chemical energy into heat energy.
- Biogas is a renewable and environmentally friendly fuel.
Real-Life Example
Biogas plants in rural households use cattle dung to produce fuel for cooking, reducing the use of firewood and LPG.
19. Which pair consists only of renewable energy sources?
Answer: B. Solar, Wind
Solar and wind energy are renewable sources because they are continuously replenished by natural processes. Solar energy is obtained from sunlight, while wind energy is produced due to the movement of air caused by the uneven heating of the Earth’s surface. Both sources generate electricity without burning fossil fuels, making them environmentally friendly and sustainable for long-term energy production.
Quick Revision
- Solar and wind are renewable energy sources.
- Both generate clean electricity with minimal pollution.
- They help reduce dependence on fossil fuels.
Real-Life Example
Hybrid renewable energy projects combine solar panels and wind turbines to provide a more reliable supply of electricity throughout the year.
20. Which statement about renewable energy is correct?
Answer: C. It is naturally replenished.
Renewable energy comes from natural resources that are continuously replaced through processes such as sunlight, wind, flowing water, and plant growth. Unlike fossil fuels, renewable resources do not get exhausted when managed properly. Their use helps conserve non-renewable resources, reduce environmental pollution, and promote sustainable development. As a result, renewable energy is becoming increasingly important in meeting the world’s future energy needs.
Quick Revision
- Renewable energy is naturally replenished.
- It supports sustainable development.
- It reduces pollution and conserves fossil fuels.
Real-Life Example
India is rapidly expanding solar parks, wind farms, and hydroelectric projects to increase the share of renewable energy in electricity generation.
Further Reading:
To deepen your understanding of energy-related concepts and their applications, refer to the NCERT Class 9 Science textbook. It provides clear explanations, illustrations, and examples that help strengthen the fundamentals required for TNPSC General Science preparation.
Looking for a TNPSC Physics Energy Test to check your preparation? This quiz features important TNPSC Physics Energy questions based on the General Science syllabus. Whether you’re preparing for TNPSC Group 1, Group 2, or Group 4, these carefully selected MCQs will help you revise key concepts, strengthen your TNPSC Physics fundamentals, and build confidence for the TNPSC examination.