The ability to do work is called energy. The most of activities in contemporary life require energy.
For comfort and convenience, we consume energy in the form of fossil fuels, electricity, and firewood. Different forms of energy are discussed below.
Different forms of Energy
There are different forms of energy.
1. Mechanical Energy
The ability of an object to do mechanical work is called its mechanical energy. There are two types of Mechanical energy – Kinetic energy and Potential energy. Mechanical energy is measured by the sum of Kinetic and Potential energy.
Kinetic energy: The ability of a moving object to do work for its motion is called the Kinetic energy of that object. If a rock is thrown against a window, the rock cannot penetrate the window. But throwing a rock can break a windowpane, because motion gives the rock kinetic energy, and that’s what enables it to do work.
Potential energy: The ability of an object to act on its position or shape is called the Potential energy of that object. River water is held back by dams at higher elevations, storing Potential energy in the water, which is converted into kinetic energy as the water descends. Winding the watch compresses the watch spring. As a result, Potential energy is stored in the spring for deformation. Using that stored energy, the clock starts to run, that is, to work. These are examples of Potential energy.
2. Heat energy
Various functions are performed with the help of heat. Engines run by turning water into steam with heat. So, heat is a form of energy. Again, the heat generated by the combustion of diesel and petrol is used to run automobiles and aeroplanes.
3. Light energy
Many chemical changes can be made with the help of light. With the help of sunlight, the tree produces food in its green leaves. So, light is a form of energy.
4. Sound energy
Sound moves the particles of the medium through which it passes. As a result, waves are created and sound is spread around. During the war, the vibration caused by the loud explosion of the bomb often broke the window panes. Sound is produced by vibrating strings in stringed instruments such as zithers, violins, etc. In these cases, mechanical energy is converted into sound energy. So sounds are a form of energy.
5. Magnetic energy
The energy stored in a magnetic field is called Magnetic energy. Iron is attracted to the magnet by magnet attraction. So, magnetism is a type of energy.
6. Electric Energy
Numerous works are done with the help of electricity. With the help of electricity fans run, lights turn on, and trains run. Electricity is essential energy in factories. So electricity is a kind of energy.
7. Chemical Energy
The energy released in a chemical reaction is called chemical energy. The chemical reactions that occur when coal, petrol etc. are burned produce heat and light energy. Chemical reactions in batteries produce electrical energy.
8. Nuclear energy
When the nuclei of heavy elements such as uranium, plutonium etc. are split by neutrons, the new elements formed are less in mass than the previous elements. This reduced mass is converted into energy according to the formula E = mc2. This energy is called nuclear energy. At present electricity is generated with the help of nuclear energy.