Energy - Definition, Types, Difference, FAQs
What is Energy and Power in Science?
Energy Definition in Physics: The ability to do work is called energy. Rate of doing work is called power. Power can also be defined as the rate of change of energy. An object can have value for the power without doing any work.
Energy Units
According to the Units (SI) metric system energy unit is called as Joule (J). Energy is also expressed in many other non-SI system units. Many of these units include calories, ergs, kilowatt-hours, kilocalories, and British Units Thermal. However, this will require a feature if we would like to specify them in SI units. All of them are employed in certain areas of Commerce and Science.
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Energy Sources
Energy sources are classified as renewable or non-renewable:
Renewable energy sources will be easily replenished.
Non-renewable energy sources can be easily filled.
Renewable and non-renewable energy sources are being used as primary energy sources to provide useful energy such as heat or they will want to produce secondary energy sources such as electricity.
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Energy Conservation Law
The total energy of an isolated system is constant despite internal changes
Work and Energy Theorem
The net work done by the forces on a body equals the change in its kinetic energy.
Did you know?
One of the basic energy measurement blocks is called the Btu or British heating unit. Btu is often defined as the amount of heat energy it often takes to raise the temperature of 1 kg of water by 1 degree Fahrenheit of the deformed level. One Btu is equal to one lucifer with black tips. It takes about 2000 Btu to create a pot of coffee. Power can be measured even in joules (similarly referred to as ‘gems’). One joule is the amount of energy needed to lift a pound of 9 inches. It takes 1000 joules, the equivalent of Btu. It can take 2 million joules to make a pot of coffee.
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What are the different forms of Energy?
There are many different types of energy, which fall into two main categories: Potential and kinetic. Let's look at the different types of energy and examples.
Kinetic Energy
Kinetic force can be defined as the force of motion. When an object is in a state of motion, it is said to have kinetic energy. For example, running water, a moving ball, and more.
The equation of kinetic energy may be:
½ m x v²
When v is the velocity of an object, and m the weight of an object.
Mechanical Energy
Mechanical Energy = Kinetic Energy + Potential Energy,
Power equipment = ½ m x v² + mgh
Chemical Energy
Energy is stored in chemical compounds, such as molecules and atoms. In the same environment as a given temperature, energy can be released or absorbed due to the reaction between a group of chemical substances equal to the difference between the reactants and the energy content of the products. When a chemical reaction occurs, this energy is released.
Once the chemical energy is released from an object, it is usually converted into something completely new.
Other forms of energy are Magnetic, Electric, Nuclear, Radiant, Elastic, Ionization, Thermal, Gravitational, and Heat & Mechanical work. Chemical energy can also be used in food and wood and stored in Biomass, Coal, Chemical batteries, and car airbags.
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Light energy
Light energy is a type of electrical radiation. Light contains photons produced when the atoms of an object heat up. Light travels in waves and is the only source of energy visible to the human eye.
Light is made up of photons, which are small packets of energy. When the atomic matter is heated, photons are produced by the movement of atoms. Photons are produced according to the temperature of an object.
Heat Energy
Heat energy can also be called thermal energy, which is produced when rising temperatures cause molecules and atoms to move faster and more precisely.
The energy that emanates from the heat of an object is known as heat energy.
Other examples of hot energy are heat from the sun, a cup of hot chocolate, baking in the oven, and heat from a heater.
These are other forms of energy and in addition, there are different types of energy.
Different Types of energy Sources
Energy sources are also used as fuel. This fuel is used in automobiles, machinery, and many other industries. They are used in hot plants to generate electricity. Energy resources can be divided into two types: non-renewable and renewable. The types of energy sources are given below.
Other types of energy based on their resources are given below.
Coal | Hydrogen | Solar |
Bioenergy | Nuclear | Wood |
Global warming | Natural Gas | The wind |
Electrical power | Fat |
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NCERT Physics Notes:
Frequently Asked Questions (FAQs)
Gravity is stored at the height of an object
e.g. high gravity is stored on heavy and elevated objects. When someone climbs into a cliff and picks up speed, the force of gravity turns to the force of motion. Hydropower is another example of gravity, in which gravity forces water down a propeller to provide electricity.
Motion power is stored within the flow of objects. As soon as they go, a lot of energy is saved. It takes energy to persuade a moving object, and energy is released when the object is slow-moving. The wind is an example of the power of movement. A striking example of the force of movement can be a car collision - The car puts on a complete stop and releases all its movement power without delay in an uncontrolled moment.
According to the law of conservation, "Energy is not created, or destroyed, but can be changed from one form to another."
The energy we use is simply the conversion of other species. It has no specific sources. However, most of the energy we have used is the result of the Sun.
Looking at the representation above, it is clear that we need power. We get this energy from eating food, which is also derived from plants and animals. In fact, all animals, plants, fungi, viruses, bacteria, and other organisms need the energy to do all they can.
Other sources of renewable energy are solar energy, wind power, biomass and hydropower. It is called renewable because it is continuous. It is also called another form of energy as these are other forms of renewable energy.
Gravity is stored at the height of an object
e.g. high gravity is stored on heavy and elevated objects. When someone climbs into a cliff and picks up speed, the force of gravity turns to the force of motion. Hydropower is another example of gravity, in which gravity forces water down a propeller to provide electricity.
According to the law of conservation, "Energy is not created, or destroyed, but can be changed from one form to another."
The energy we use is simply the conversion of other species. It has no specific sources. However, most of the energy we have used is the result of the Sun.
Looking at the representation above, it is clear that we need power. We get this energy from eating food, which is also derived from plants and animals. In fact, all animals, plants, fungi, viruses, bacteria, and other organisms need the energy to do all they can.
Other sources of renewable energy are solar energy, wind power, biomass and hydropower. It is called renewable because it is continuous. It is also called another form of energy as these are other forms of renewable energy.
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Questions related to
Hello there,
Emasters is a new form of education introduced in a very few NITs and IITs. Emaster in Renewable Energy is offered in IIT Kanpur. IIT Kanpur is the first IIT to introduce Emasters in Renewable Energy. Kindly check out their official site to get more information.
https://emasters.iitk.ac.in/course/masters-in-renewable-energy-and-emobility
Renewable resources of energy are sources of power that can be replenished naturally and do not deplete thr earth's resources. Some of these are solar energy that is harvested from sun, wind energy which is generated by wind turbines, hydropower which is produced by capturing the energy of moving water, biomass energy which is created from organic materials like plant and animal waste and tidal energy which is generated from movement of tides.
On the other hand the sources of energy that are finite in quantity and cannot be replenished on a human timescale once they are consumed are not the sources of renewable sources like fossil fuels and nuclear energy.
Correct Answer: Both statements are true.
Solution : The correct answer is (a) Both statements are true.
Statement 1 accurately states that geothermal energy is a renewable source of energy derived from the heat of the Earth's interior. Geothermal energy is generated by tapping into the heat stored within the Earth's crust, which is a virtually limitless and continuously replenished resource.
Statement 2 is also true. Geothermal power plants harness geothermal heat and convert it into electricity using steam turbines. The process involves drilling wells to access hot water or steam reservoirs underground. The hot water or steam is then used to drive turbines, which generate electricity.
Both statements provide accurate information about geothermal energy and its conversion into electricity.
Correct Answer: Electrical energy
Solution : The correct option is electrical energy.
The photovoltaic effect is a mechanism used by photovoltaic cells, also referred to as solar cells, to transform light energy from the sun directly into electrical energy. When photons, the light particles hit a solar cell's surface, their energy is transferred to the material's electrons, causing this effect. These electrons get activated by the energy of the photons, which causes them to flow as an electric current. The generated current can then be harnessed and used to power electrical equipment, or it can be stored in batteries for later use.
Correct Answer: productive
Solution : The correct choice is the fourth option.
Explanation: The term productive means achieving or producing results, which fits well with the context of evaluating social media use. It suggests assessing whether the use of social media contributes to positive and meaningful outcomes.
Therefore, the correct word to fill in the blank (4) is productive.
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