Chapter-14 Source and Energy

Explanation:

Once upon a time, wind energy was harnessed and used by windmills to carry out mechanical activities like lifting or well water extraction. Nowadays, though, windmills are used to generate power. Wind kinetic energy is gathered and converted into electricity with the help of the rotatory motion of the blades, spinning the turbine of the electric generator to produce power.

Waterfalls were formerly used to generate potential energy. Yet, because there are fewer waterfalls nowadays, water dams are constructed and used as a source to harness the potential energy. Here, water falls onto a turbine creating power from a specific height.

Explanation:

 A good energy source possesses the qualities listed below:

• Being economical

•  being easy to transport and store.

•  being simple to access

• having a lot of work done per unit of mass or volume.

  
  

Explanation:

When fuel is readily available and provides a lot of heat energy when burned, it is said to be good fuel.

Fuel is flammable material that mostly contains carbon. Fuel releases a significant quantity of energy in the form of heat and light upon effective combustion in the presence of air. Fuels may be divided into several categories, such as natural and synthetic fuels. Massive amounts of energy are produced by fuels, and this energy is economically employed for a variety of residential and industrial uses.

When we burn a piece of paper with a matchstick, for instance, the flame creates light. If we examine carefully, light energy is not produced there; rather, it results from the conversion of the heat energy of the matchstick into light energy. Because of this, people constantly need certain materials to change one type of energy into another in order to do a variety of jobs.

Explanation:

The following are some benefits of using natural gas for cooking and heating:

• Usage is easy.

• It is offered conveniently.

• easy to carry.

• It doesn't produce a lot of smoke when burned.

• It is quickly ignited.

  
  

Explanation:

The following are some disadvantages of fossil fuels:

Fossil fuels, such as coal and petroleum, release a considerable quantity of pollutants into the atmosphere, which contributes to air pollution.

Carbon dioxide and other gases are released when fossil fuels are burned, and these gases cause global warming.

Fossil fuel emissions include carbon, nitrogen, sulphur, and other oxides that affect both soil fertility and drinking water quality.

Explanation:

We are seeking for alternative energy sources since fossil fuels are non-renewable and hence not readily available in large quantities or easily replenished. They will run out if fossil fuel usage is not controlled. Hence, switching to a new energy source is desirable.

We are seeking other energy sources because

• Energy sources that are fossil fuels cannot be replenished.

• They cannot be replaced and are not widely accessible.

• If fossil fuel usage is not controlled, they will run out.

  
  

Explanation:

Solar cookers use sunlight as a source for both cooking and heating. Mirrors are used to reflect and focus the sunlight in one area. A concave mirror can therefore be used in a solar cooker since it concentrates all the sunlight at one spot, raising the temperature and, as a result, heating and cooking the food.

Explanation:

The different types of energy that can be obtained from water include tidal energy, wave energy, and ocean thermal energy. The energy produced by the ocean is subject to the following limitations:

• The relative locations of the earth, sun, and moon have an impact on the tidal energy.

• High dams are required to turn tidal energy into electricity.

• To harness the power of wave energy, strong waves are required.

• To efficiently capture ocean thermal energy, hot surface water and cold water at a depth should be at least 20°C apart.

  
  

Explanation:

Geothermal energy is the name for the energy that originates from the earth. The energy can come from the hot spots formed as the molten materials at the earth's core are pushed towards the crust. Geothermal power plants use hot springs as a heat source to produce electricity.

Geothermal energy is created by the earth's core's slow radioactive particle decay, which occurs in all rocks.

Scientists have found that the deep core of the planet is around 10,800 degrees Fahrenheit (°F) hotter than the sun's surface. Around the mantle-crust barrier, the temperature in the mantle ranges from about 392°F to about 7,230°F. Magma that is underground absorbs heat through rocks and water. The warmest rocks and water are those that are located deeper beneath.

Explanation:

A 100% pollution-free energy source is impossible. While being thought of as pollution-free, solar cells can nonetheless harm the environment during production. There is no waste left over after fusion in the case of nuclear energy. The wastes created by fission, however, are dangerous. This means that no energy source is pollution-free.

Explanation:

Hydrogen gas is cleaner than CNG, which includes hydrocarbons. Carbon pollution is the result of using CNG. On the other hand, neither the fusion of hydrogen nor the substance itself produces any waste. Hence, hydrogen is a cleaner rocket fuel than CNG.

Explanation:

The following two energy sources are limited and exhaustible:

Wood is sourced from forests. Deforestation has resulted in fewer forests. We are aware that it takes a number of years for trees to develop. The availability of wood will decrease as the rate of deforestation increases. Hence, wood is a limited supply of energy.

Extinct plants and animals that have been buried for a very long time are used to make coal. Due to rising demand brought on by industrialisation, coal is in limited supply. Hence, coal is a limited resource of energy.

Explanation:

The following traits define a perfect energy source:

It ought to be economical.

It should be available.

without pollutants.

straightforward travel and storage.

There should be a large quantity of energy produced when burnt.

Explanation:

Advantages:

The solar cooker's heat source is sunlight. It is a clean, renewable, and limitless source of energy. As it is constantly accessible, it is economical.

Its disadvantage is that cloudy days render it useless.

Explanation:

 b) a gloomy day,

A solar water heater heats water using solar energy. On a cloudy day, the sunlight won't be strong and brilliant enough, and the clouds will reflect some of it back into the sky. As a result, the sun cannot reach the earth. As a result, the solar water heater won't be able to heat the water using solar energy.

Explanation:

Animal waste and dead plants are sources of biomass. As they interact with water and sunlight, these dead plants and animals undergo a chemical change. Nevertheless, nuclear energy is produced through the fusion and fission of atoms, which unleashes a massive amount of energy. Without sunshine, nuclear fusion and fission are both possible.

A plant's parts include wood, gobar gas is made from animal manure, and dead plants and animals' remnants are used to make coal. These are all biomass energy products as a result.

Explanation:

a) Windmills are used to capture wind energy. The fact that windmills need to be moving at a speed of more than 15 km/h is one of the drawbacks of using wind energy. Moreover, there will be additional windmills to cover a larger region.

b) Waves: Very powerful ocean waves are required to harvest energy from the waves.

c) Tides: The sun, moon, and earth must be in a straight line, and the tides must be very powerful, in order to harness the energy of the tides.