Question

Give short answers:
What is fuel?

Answer 1

Hint : Fuel exists in all three forms depending upon the requirement of the user. Fuel of different kinds are found in solid, liquid and even in gaseous form. Most fuels are natural, but artificial fuels can also be made for specific operations.

Complete Step By Step Answer:
Fuel is a substance which upon burning or using gives heat and energy. The energy or heat that a fuel releases is utilized in various applications.
As energy can neither be created nor be destroyed, we use fuel as substances which can transform one form of energy into another which can be utilized. For example, when we burn something the substance gets lit up with fire, this gives us heat energy and light energy. The heat energy is produced because of the light energy.
Thus, the thing used to burn something is called a fuel. We need some kind of fuel every time we need to convert one kind of energy into another, without the help of fuel we cannot transform one form of energy into the one which we want.
Fuels are available in all three forms, solid, liquid and gas. Wood and coal can be considered as natural solid fuel, charcoal and straw can be considered as artificial solid fuel.
Petroleum is considered as natural liquid fuel, liquid extracted from petroleum such as petrol, diesel are considered as artificial liquid fuels.
Natural gas is considered as natural gaseous fuel, coal gas, water gas, oil gas, etc., are considered as artificial gaseous fuels.

Note :
Fuels can also be classified as fossil fuels, biogas, nuclear energy fuels, etc., there are also renewable and non-renewable fuels, such as fossil fuels are non-renewable as they can exhaust someday in the future, solar and wind energy are renewable fuels as they cannot exhaust even in the distant future.