Energy is the ability of a physical system to do work.
The total energy of any object can be identified with its mass.
We use energy to do work and make all movements.
When we eat, our body transforms the food into energy.
There has been an enormous increase in the demand for energy since the middle of the last century as a result of industrial development and population growth.
Due to the problems associated with the use of fossil fuels, alternative sources of energy have become important and relevant in today’s world.
Solar Energy, Geothermal Energy, Wind Energy, Biomass Energy etc. are some different sources of energy.
Topics covered in this snack-sized chapter:
In the context of physical sciences, several forms of energy have been defined. These include:
These forms of energy may be divided into two main groups:
Potential energy is stored in a body and has potential to work.
- Electromagnetic energy or Radiant energy
Chemical Energy stored in things like the food we eat, fossil fuels and explosives.
Elastic energy stored in a stretched elastic band or spring, like rubber band.
Nuclear energy stored in the nucleus of atom. This energy is used in nuclear power stations to generate heat.
Thermal energy is the part of the total internal energy of a thermodynamic system or sample of matter that results in the system temperature
The kinetic energy of an object is the energy which it possesses due to its motion.
It is defined as the work needed to accelerate a body of a given mass from rest to its stated velocity.
If someone kicks a ball hard and if it hits your body, it hurts, because your body has to suddenly absorb all that energy and stop the ball.
Types of Potential Energy
Electrical Energy: This is kinetic energy of moving charges like energy flowing through a light bulb.
Light and other radiation are called electromagnetic energy they are also form of kinetic energy.
“Energy can be changed from one form to another but can’t be created or destroyed”
This law is followed everywhere in energy chain.
Like in simple light bulb electrical energy changes into light and heat energy.
Sun is the source of energy; all the living things get energy from the sun.
Energy we get from the sun is called solar energy.
All of our energy sources plants, animals, everything on our planet directly or indirectly takes energy from sun.
Solar energy is used to produce electricity.
Solar cells are used to store electricity produced from sun.
We are using solar energy for street lights.
There is an enormous usage of solar energy, as it is never going to end.
All our requirement of energy is fulfilled by sun.
Energy sources which are not going to end by their usage are called renewable source of energy.
Renewable energy is captured from an energy resource that is replaced rapidly by a natural process
Like power generated from the sun or from the wind.
Currently, the most promising alternative energy sources include wind power, solar power, and hydroelectric power.
Other renewable sources include geothermal and ocean energies,
Biomass and ethanol are also used as renewable fuels.
Wind power is the conversion of wind energy into a useful form of energy, such as using wind turbines to make electricity
It increased exponentially due to significant breakthroughs in turbine technologies
Wind energy is a clean and renewable source of power.
Hydroelectric energy from water is possible due to the gravitational potential energy stored in water.
The principle is simple: the force of the water being released from the dam spins the blades of a turbine.
The turbine is connected to the generator that produces electricity.
Renewable Energy: Hydroelectric
Geothermal Energy relies on heat produced under the surface of the Earth.
Geothermal plants depend on steam to power turbines and generate electricity.
It is though the method of producing steam.
Source of energy which is not going to replace or replace very slowly after we use are called nonrenewable source of energy.
Nonrenewable source has finite supply and it is used faster than it can replenish.
Fossil fuels and oil are examples of nonrenewable source of energy.
Renewable Energy: Geothermal
Humans rely heavily on fossil fuels for a source of energy.
Fossil fuels and Oil are formed of dead plant vegetation that over many, many years came to be buried under layers of earth.
Coal is a nonrenewable energy source because it takes millions of years to create.
The energy in coal comes from the energy stored by plants that lived hundreds of millions of years ago.
Nonrenewable energy source: Coal
Diesel is a petroleum fuel that contains energy.
At refineries, crude oil is separated into different fuels including gasoline, jet fuel/kerosene, lubricating oil, heating oil, and diesel.
Gasoline is a nonrenewable fuel made from petroleum.
Oil was formed from the remains of animals and plants that lived millions of years ago in a marine (water).
The entire petroleum product we use is made from refining this oil.
Nonrenewable energy source: Oil