Correct Answer is : $(c)$ nuclear energyExplanation:Biomass$\rightarrow$Biomass is the organic matter like dead parts of plants and trees and the waste material of animals which are used as a fuel to produce energy. Examples of biomass energy:Wood, agricultural wastes, cow dung, and biogas are some examples of biomass energy.Nuclear energy$\rightarrow$Nuclear energy $(Atomic\ energy)$ is also known as nuclear energy refers to the energy released through fission and fusion of the nucleus of an atom to generate heat and electricity.Examples of Nuclear energy-Solar energy produced due to nuclear fusion and electricity generated by an atomic reactor are examples of nuclear energy.Therefore, nuclear ... Read More

Correct Answer is : $(b)$ geothermal energyExplanation:Geothermal energy$\rightarrow$Geothermal energy is the heat energy obtained from hot rocks present inside the earth due to the fission of radioactive materials in it. So, it does not come directly or indirectly from the sun's energy.The term Geothermal is derived from the two Greek words, 'Geo' meaning "earth" and 'thermal' meaning "heat".Production of geothermal energy$\rightarrow$Geothermal energy is the heat produced deep in the Earth's core, which is a clean, renewable source of energy that can be harnessed for use as heat and electricity. The heat in the core is produced mainly by the radioactive ... Read More

Comparison between the sun and fossil fuels as sources of energy:The SunFossil Fuels1. It produces an enormous amount of heat due to the occurrence of nuclear fusion inside it.1. They are formed from the remains of dead plants and animals.2. It does not cause any air pollution.2. They cause air pollution by burning.3. It is a renewable source of energy.3. They are non-renewable sources of energy.

Comparison and contrast between biomass and hydroelectricity as sources of energy are as follow:Biomass Hydroelectricity 1. It is generated from organic matter including wood, agricultural waste and cow dung.1. It is produced from the potential energy of water stored at a height.2. It is a renewable source of energy.2. It is also a renewable source of energy.3. It can be used for only heating and cooking.3. It can be used for running all types of electrical appliances.4. It can be obtained without using any special device.4. It can be produced only by establishing a hydro-power plant.5. Its burning causes air pollution.5. It does not cause any pollution.Read More

Wind:The wind is the flow of air and is a source of energy. It possesses kinetic energy. Wind possesses kinetic energy, and when the fast-moving wind strikes the wind turbine it starts rotating, thus the kinetic energy of wind is converted into mechanical energy. Further, the wind turbine is connected to electricity generators through the shaft, due to which it also rotates and drives the generator which produces electricity. Finally, the mechanical energy gets converted into electrical energy.Advantages of wind energy:The two advantages of using wind energy for generating electricity are as follows:1. It is a clean source of energy as it ... Read More

$(a)$ Renewable Energy:A renewable source of energy is defined as the sources of energy that are being produced continuously means they are inexhaustible in nature and can be used for a very long period of time are called renewable sources of energy.Examples: Wind Energy, Solar Energy, Hydro Energy, and Biomass. Non-renewable Energy:They are non-renewable because they are present in limited amounts in nature, and once exhausted, cannot be replenished or regained.Non- Renewable sources of energy - Coal, Petroleum, Natural gas. Renewable sources of energy - Wind, Tides, Wood.The difference between a renewable and a non-renewable source of energy are:Renewable Source of EnergyNon-Renewable Source of Energy1. It can be used again and again ... Read More

A source of energy is defined as the source which can provide an adequate amount of energy in a convenient form for a long period of time.The two main categories of sources of energy are:(i) Renewable source of energy.       (ii) Non-renewable source of energy.On the basis of availability, natural resources are divided into two types:1. Renewable- These types of resources are available in infinite quantity and can be replenished naturally and used repeatedly. Example- Sunlight, wind, water, etc.2. Non-Renewable- These types of resources are limited because either they form slowly, or do not form naturally in the environment due to their non-renewable nature. Their availability may run ... Read More

The advantages of solar cells are as follows:1. They do not have moving parts and require no maintenance.2. They can be used even in remote and inaccessible areas.3. It saves fossil fuels like coal, kerosene, petroleum, etc, which are non-renewable.4. It does not produce any harmful smoke and ash that pollutes the air.5. It does not spoil the nutrients present in the food.The disadvantages of solar cells are as follows:1. They are very expensive, as they require a special grade of silicon or silver wire.2. They are less efficient, as they can convert only about 25% of the light falling on ... Read More

The environmental consequences of the increasing demand for energy are as follows:1. Setting up more nuclear power plants increases the radioactivity in the environment.2. Construction of hydropower plants is disturbing the ecological balance.3. The combustion of fossil fuels causes acid rain, due to which plants, soil, and aquatic life get damaged.4. The combustion of fossil fuels also increases the greenhouse gasses (carbon dioxide) which pollute air present in the atmosphere.Steps for reducing energy consumption are given below:1. Switch off all the electrical devices such as TV, lights and fans when not needed.2. Energy-efficient electrical appliances should be used.3. Solar cookers and pressure cookers should be used for ... Read More

Given:An oil funnel made of tin sheet consists of a \( 10 \mathrm{~cm} \) long cylindrical portion attached to a frustum of a cone. The total height is \( 22 \mathrm{~cm} \), diameter of the cylindrical portion is \( 8 \mathrm{~cm} \) and the diameter of the top of the funnel is \( 18 \mathrm{~cm} \).To do:We have to find the area of the tin sheet required to make the funnel.Solution:Diameter of the upper circular end of frustum $= 18\ cm$This implies, Radius of the upper circular end of frustum $(r_1) = 9\ cm$The radius of the lower circular end ... Read More