what is energy??

Energy: energy is an essential requirement of our life. No activity in our life can be under taken without the use of energy. Energy is one or the other form has been used by a man since long. We use heat energy obtained by burning fuel like wood, coal, kerosene or cooking gas for cooking our food. The energy of fuels fuels like petrol and diesel is used to run cars, buses, trucks and trains. Diesel is also used to provide energy to run pumps set for irrigation in agriculture .coal, fuel oil or natural gas are used to provide energy in factories and run thermal power plants. Electrical energy (or electricity) is use for lighting bulbs and tubes, and to run radio, television, household appliances, electric trains and factory machines. In fact, all our everyday activities use energy in one form or the other. And if there is no energy, all our activities will come to a stop. For example, if there is no energy, we won’t be able to cook food. If there is no energy, we won’t be able to run cars, buses, trucks, trains and aeroplanes. And if there is no energy, we won’t be able to run machines in factories, power plant or pump set in agriculture.so, energy is essential for our survival in this world. A source of energy is one which can provide adequate amount of energy in a convenient form over a long period of time. Thus, we can say that energy is required in every field. Usually, energy in the form of fuel and electricity is used to carry out the activities mentioned above. Energy can be derived from various sources. However, the sun is the ultimate source of all forms of energy. All the sources of energy can be divided into two main categories: renewable sources of energy and non-renewable sources of energy.

Renewable sources of energy: The sources of energy which are inexhaustible (i.e. which can never be finished) and are being continuously supplied by nature are known as renewable sources of energy.

Example: wind, flowing water, the sun, ocean tidals energy, interior of the earth, biogas, plants, vegetable waste etc. the sources of energy is also known as non-conventional sources of energy.

Non-renewable sources of energy: the sources of energy which are exhaustible (i.e. which can be finished) and have been formed in nature long ago are known as non-renewable sources of energy.

Example: coal, petroleum, natural gas, fissionable materials like uranium. These sources energy are also known as convectional sources of energy.