Every matter in the universe is composed of tiny particles called molecules. They attract each other with some attractive force. There exists an intermolecular force of attraction between molecules. All matters in the universe are considered as a physical system. These are analyzed by the laws of physics. Every object in the universe cannot move without external force. If force is applied to the object. It will be stored inside and then released in the form of work.
The capacity of the physical system that needs to do work is called the energy of the system and it is a scalar quantity. It occurs in many forms. The S.I unit for energy is Joule. Energy is used to power the devices that we are using such as heat, light, etc. The different types of energy sources are used mainly for the production of electricity.
Energy sources can be divided into two categories such as renewable and non-renewable sources. Renewable sources of energy are the energy that is obtained from flow sources such as wind, tide, sunlight, etc. The energy that is obtained from natural resources which cannot be replaced is called non-renewable sources of energy. Fossil fuels and nuclear energy are some examples of non-renewable sources.
Energy is a fundamental quantity that is very important for life. Energy conversion is the process of conversion of one form of energy into another form of energy. All forms of energy-related to motion. By the conservation of energy law, one form of energy can be transformed into another form and the energy cannot be destroyed or formed. In other ways, it can also be stated that if the system is isolated then the total energy of the system does not change and it remains constant.
Energy is very important and it occurs in nature in many forms. There are different kinds of energy. They are mechanical energy, thermal energy, nuclear energy, chemical energy, electromagnetic energy, sonic energy, gravitational energy, kinetic energy, potential energy, and ionization energy. Generally, all energy comes under potential or kinetic energy.
If the body moves from one place to another then it has kinetic energy. It is always a positive value. The kinetic energy is given by,
$$\mathrm{K.E.=\frac{1}{2}mv^{2}}$$
This is the energy of the body by virtue of its position. Example: a book on the table. The potential energy is given by,
$$\mathrm{P.E.=mgh}$$
This is the energy required for the binding of electrons to the nucleus of the atoms or molecules.
The potential energy stored in the is converted into mechanical energy. It is the addition of kinetic energy and potential energy.
$$\mathrm{Mechnical\:energy=\frac{1}{2}mv^{2}+mgh}$$
This energy is due to the temperature difference between the two systems. It is due to the movement of atoms in the system.
This is the energy that results from the nuclear reaction of the materials. Examples of nuclear energy are nuclear fusion and nuclear fission.
It is the energy formed due to the chemical reaction between atoms or molecules. The chemical reaction is formed when the chemical bond between the atoms gets created or destroyed.
This energy is formed from light or electromagnetic waves. X-rays and gamma rays are some examples of electromagnetic energy
This energy is formed from sound waves. It travels through the air.
Gravity is the attraction between any two bodies in accordance with their mass. The energy associated with this gravity is gravitational energy.
There are many types of energy in our environment. One form of energy can be transformed into another form. The conversion between these energies is given below.
The light energy is converted into thermal energy
Mechanical, heat, and light energy are derived from electrical energy.
Nuclear energy is transformed into light and heat energy.
Thermal energy is transformed into heat energy.
Solar energy is transformed into heat, chemical, and electrical energy.
Chemical energy is transformed into electrical energy.
Mechanical energy is converted into electrical and potential energy.
Gravitational potential energy is converted into kinetic energy.
If the ball is dropped down then the potential energy stored in the ball is transformed into kinetic energy.
The mechanical energy due to the movement of water is transformed into electrical energy.
While driving the car the chemical energy stored in the battery is transformed into mechanical energy.
In a battery cell the chemical energy is converted into electrical energy.
Heat energy from the sun is used in a battery to store electrical energy.
During the explosion nuclear energy is converted into heat and light energy.
In ancient times the first conversion was made by the use of fire. They use the fire by burning the dried plant and animal waste for cooking and heating. It takes many years for the invention of energy conversion after the use of fire.
In earlier times our ancestors used a machine to grind the grains. Pot making is also an example of this conversion. Later the invention of watermills came from this. The water which rotates the wheel produces mechanical energy which is converted to electrical energy.
Windmill is also an example of the evolution of conversion of energy.
Steam engine is the first device that was constructed for the conversion of thermal energy into mechanical energy. After some years it was developed more and the techniques were improved.
In this article the facts about the energy, types of energy, and energy conversions are discussed in detail. The types of energy conversion and the examples for energy conversions are also discussed. The evolution of energy conversion and energy conversion at the industrial level is also discussed.
Q1. Give some examples for the conservation of energy.
Ans: In the explosion of dynamics, the chemical energy stored in it is converted into kinetic, heat, and light energy. The total energy calculated by adding the kinetic energy, heat energy, and light energy is equal to the initial chemical energy. Similarly in a loudspeaker, the electrical energy is converted to sound energy.
Q2. What are the consequences of the conservation of energy?
Ans: The first main consequence is that the perpetual motion of the system cannot exist. That is, it is not possible for a machine to continuously deliver energy without any disturbance. All systems do not have translation symmetry. So the conservation of energy is not possible for all systems.
Q3. Give some daily-life examples for energy conversion.
Ans: The nuclear energy of the sun is converted into light energy and heat energy. In hydroelectric dams, the kinetic energy of water is transformed into electrical energy. In bungee jumping the gravitational potential energy is converted into elastic potential energy.
Q4. Differentiate renewable and nonrenewable sources.
Ans:
| Renewable sources | Non- Renewable sources |
|---|---|
It can be reusable | It cannot be reusable. |
It will not exhaust | Continuous usage leads to be exhausted |
It is in unlimited quantity | It is in limited quantity |
Low-cost | High cost |
Q5. Why is there a need for an alternate source of energy?
Ans: Fossil fuels are non-renewable sources of energy that are reducing in quantity for continuous usage. These sources need thousands of years to form again. So they are exhausted. To save these sources for the future it is better to go for an alternate source.
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