This PSEB 10th Class Science Notes Chapter 14 Sources of Energy will help you in revision during exams.
PSEB 10th Class Science Notes Chapter 14 Sources of Energy
→ No activity is possible without energy.
→ Renewable sources of energy are sun, water, and wind, etc.
→ Substances having low ignition temperatures are called inflammable substances.
→ Substances burn at a moderate rate during slow combustion. Substances burn in a very short span of time during rapid combustion.
→ During spontaneous combustion substances suddenly catch fire when their temperature is raised above ignition temperature.
→ Gobar gas is produced by fermentation of cow-dung by anaerobic bacteria.
→ Gobar gas or biogas is a fuel of high calorific value.
→ Solar energy is the combination of visible infrared radiations and invisible (ultra-violet) energy radiated out by the sun.
→ Solar cookers, solar heaters, solar furnaces, and solar cells are devices using solar energy.
→ Solar cells convert solar energy directly into electric energy. Solar cells are used to supply electric energy to watches, calculators, and satellites.
→ Excessive use of any source of energy disturbs the environment. We should try to use non-polluting (clean), economical and efficient sources of energy.
→ Non-polluting sources of energy like solar and wind energy need to be promoted.
→ It is neat and clean energy which is available free of cost.
→ Energy: The capacity of doing work is called energy.
→ Kinetic Energy: It is the energy possessed by a body due to motion, e.g., moving air, running water, etc.
→ Solar Energy: The energy obtained from the sun.
→ Wind Energy: The kinetic energy contained in a large mass of air in motion is called wind energy.
→ Solar Cooker: It is a device that uses solar energy for cooking food.
→ Solar Cell: A device that converts solar energy into electric energy.
→ Ocean Thermal Energy (O.T.E.): There is always the same temperature difference- between water at the surface of the ocean and water at the depth. This difference can be even 20° C. The energy available in this form is called ocean thermal energy.
→ Salinity Ingredients: The variation of concentration of salt is called salinity ingredient.
→ Fuel: Those substances which burn to produce heat energy are called fuels.
→ Biomass: The material present in the bodies of plants and animals is known as biomass.
→ Biogas: It is a mixture of methane (CH4), Carbon dioxide (CO2), and Hydrogen Sulphide (H2S) gas. It is produced by anaerobic fermentation of plants and animals waste (Gobar) and human wastes (feaces) in the presence of water.
→ Destructive Distillation: The process of heating in the absence of air to a high temperature is called destructive distillation. From the destructive distillation of coal-coaltar, coke and coal gas are obtained.
→ Fossil Fuel: Fossil fuel is formed by dead remains of plants and animals under the surface of the earth due to changes in temperature and pressure. Coal, petroleum, and natural gas are fossil fuels.
→ Liquefied Petroleum Gas (L.P.G.): Liquefied Petroleum Gas is a domestic fuel. It is a mixture of ethane, butane, and isobutane gases.
→ Synthetic Petroleum: It is formed by the reaction of coal with hydrogen at high temperatures and pressure.
→ Ignition Temperature: That particular temperature at which a substance starts burning is called ignition temperature.
→ Calorific Value of Fuel: The amount of heat produced by the complete combustion of 1 g mass of a fuel is called the calorific value of the fuel.
→ Slurry: The mixture of gobar (cow dung) and water obtained as a residue in the biogas plant is called slurry.
→ Propellant: Rocket fuel is called propellant. It is a mixture of some concentrated fuel and oxidizing substances.
→ Tidal Energy: That energy that is produced due to the rise and fall of the water level is called tidal energy.
→ Wave Energy: That energy that is produced due to the kinetic energy of waves near the seashore is called wave energy.
→ Geothermal Energy: Due to changes in the interior of the earth, energy produced from the conversion of underground water into steam is called geothermal energy.
→ Nuclear Energy: The energy produced due to nuclear fission reactions of atoms of heavy metals is called nuclear energy.
→ Nuclear Fission: The process of splitting of an atom of the heavy nuclear element by the bombardment of neutrons into light nuclei with the evolution of energy is called nuclear fission.
→ Nuclear Fusion: The process of combining light nuclei to form a heavy nucleus with the release of energy is called nuclear fusion.
→ Greenhouse Effect: The increase of temperature of the atmosphere due to the absorption of ultraviolet rays coming from the sun by carbon dioxide (CO2) present in the air is called the greenhouse effect.