WHAT IS ENERGY AND THEIR TYPES

WHAT IS ENERGY?

Physicists, who are scientists who study force, motion and energy, say that energy is the ability to do work, and work is moving something against a force, like gravity. There are a lot of different kinds of energy in the universe, and that energy can do different things.

Energy can be found in many things, and takes many forms. There is a kind of energy called kinetic energy in objects that are moving. There is something that scientists call potential energy in objects at rest that will make them move if resistance is removed.

The molecules making up all matter contains a huge amount of energy, as Einstein's E = mc^2 pointed out to us. Energy can also travel in the form of electromagnetic waves, such as heat, light, radio, and gamma rays. Your body is using metabolic energy from your last meal as you read this.

Energy is closely related to the condition of the environment for several reasons. One is that most of the energy we use comes from fossil fuels, including coal, petroleum, and natural gas, which are found in the earth. These natural resources are not renewable—that is, once they are used up, they are gone forever. The process of gathering fossil fuels and other natural resources can be devastating to the sensitive wildlands (such as the tropical rainforests, the Arctic tundra, and coastal marshes) from which they come.

Another way that energy is linked to the environment is that its production and its use can cause environmental damage. Fossil fuels are put through a burning process called combustion in order to produce energy. Combustion causes the release of various pollutants, such as carbon monoxide and sulfur dioxide, which pose health risks and may contribute to acid rain and global warming.

The environmental impact of fossil fuels has led many people to turn to other sources of energy when possible. There are a growing number of ways in which renewable energy from the sun , the wind, and water, can be used for day-to-day needs, and these alternatives are becoming increasingly cheaper and easier to use. Some people have bought solar panels that can be connected to their homes to convert sunlight into electricity. Some have abandoned their gas-powered cars in favor of ones that are solar-powered. Many people heat their homes with wood-burning stoves instead of gas or electricity.

Another kind of energy is nuclear energy. Nuclear energy is created at power plants through a scientific process that involves splitting atoms. When an atom's nucleus is split, energy is released. This kind of energy is currently used to create electricity by boiling water to create steam that turns turbines. While nuclear power is a useful source of energy, the radiation that it produces can be harmful to people if they are exposed to high levels of it. Nuclear plants must adhere to very strict safety practices in the production of nuclear energy and the disposal of nuclear waste.

There are two sources of energy: renewable and nonrenewable energy.

Nonrenewable Sources of Energy

Most of the energy we use comes from fossil fuels, such as coal, natural gas and petroleum. Uranium is another nonrenewable source, but it is not a fossil fuel. Uranium is converted to a fuel and used in nuclear power plants. Once these natural resources are used up, they are gone forever.

The process of gathering these fuels can be harmful to the biomes from which they come. Fossil fuels are put through a process called combustion in order to produce energy. Combustion releases pollution, such as carbon monoxide and sulfur dioxide, which may contribute to acid rain and global warming.

Renewable Sources of Energy

Renewable sources of energy can be used over and over again. Renewable resources include solar energy, wind, geothermal energy, biomass and hydropower. They generate much less pollution, both in gathering and production, than nonrenewable sources.

·         Solar energy comes from the sun. Some people use solar panels on their homes to convert sunlight into electricity.

·         Wind turbines, which look like giant windmills, generate electricity.

·         Geothermal energy comes from the Earth's crust. Engineers extract steam or very hot water from the Earth's crust and use the steam to generate electricity.

·         Biomass includes natural products such as wood, manure and corn. These materials are burned and used for heat.

·         Dams and rivers generate hydropower. When water flows through a dam it activates a turbine, which runs an electric generator.