Electricity
From Simple English Wikipedia, the free encyclopedia
Electricity has two definitions, which are used in different contexts. The first definition is electricity according to physics, while the simpler definition is electrician's electricity.
The definition in physics is: Electricity is the flow of electrons in a substance.
The electrician's definition of electricity is: Electricity is the flow of positive electricity in a metal. In daily usage, electricians usually think that electricity is the flow of positive electricity, even though they know that what actually flows are the electrons. They use this explanation since it is simpler.
In physics, "Gravitation pulls things from a place that is higher to a place that is lower". This can be stated as "Electricity flows from a point where it has higher potential energy (the positive side of a battery or the place where there is more protons (+) than electrons (-)) to the place where it has lower potential energy (the negative side of a battery or a place where there are more protons (+) than electrons (-).". This can be stated even more simply as: "Energy moves from somewhere high to somewhere low."
A place that makes a lot of electricity is called a power station.
Electricity is a the field of physics that studies electrical phenomena such as electric current, electric voltage, electric resistance, etc. Almost all the time, the word "electricity" is incorrectly used instead of "electric energy", "electric current", "electric power", and many other electrical properties.
Electric charge is the property of electrons and protons. Electrons are said to be negatively charged while protons are said to be positively charged. Electric charge is a "conserved" property, meaning that it behaves like a substance and can be moved from place to place. 6,242,000,000,000,000,000 (6.242 x 10^18) electrons or protons make up 1 Coulomb of charge.
- Electric current is the uniform motion of electric charge. When 1 Coulomb of electrically charged particles move past a point in 1 second, the existing current is 1 Ampere.
- Electric voltage is the "push" behind the current. It is the amount of work per electric charge that an electric source can do. If a source can do 1 Joule of work on 1 Coulomb of charge, it has a 1 Volt of electric potential.
- Electric resistance is the ability of a substance to resist the flowing of the current, i.e. to reduce the amount of current that flows through the substance. If an electric voltage of 1 Volt maintains a current of 1 Ampere through a wire, the resistance of the wire is 1 Ohm.
- Electric energy is the ability to do work by means of electric devices. Electric energy is a "conserved" property, meaning that it behaves like a substance and can be moved from place to place. Electric energy is measured in Joules or kilowatt-hours (kwh). Electric energy is the amount of energy that an amount of electricity can produce at a time.
- Electric power is the rate at which electric energy is being used, stored, or transferred. Flows of electrical energy along power lines are measured in Watts. If the electric energy is being converted to another form of energy, it is measured in Watts. If it is stored (as in electric or magnetic fields), it is measured in Volt-Ampere-Reactive. If some of it is converted and some of it is stored, it is measured in Volt-Amperes.
Electricity is what lights the bulbs around your home, turns on your TV, computer, radio and all the other practical appliances in your household. Without electricity the world's wheels would stop running. It is the source of energy for almost all industries on earth.
Electricity is generated in places called power stations. There are many ways of generating electricity, and they can be classified into two parts,
1. Renewable energy resources 2. Non-renewable energy resources
Thermal power stations use heat to generate heat (thus comes "thermal" which means exactly that!). The heat is used to turn water into steam. The force of the steam turns giant fan-like structures called turbines, which in turn cause 'generators' to generate electricity. The heat may be generated by burning fossil fuels (sources of non-reusable energy dug from the earth Which were formed over millions of years due to high pressure and temperature on dead plants and animals buried deep inside the earth) Examples are oil, coal, natural gas. Geothermal power stations use the heat from rocks deep inside the earth to heat water in pipes in order to turn it into steam. This is done in New Zealand.
There are many other renewable sources of energy. HEP (stands for Hydro-Electric Power) uses the force of water in rivers to turn turbine which turn generators. HEP schemes are found across the Amazon River in Brazil. Wave energy is another option where the force of sea waves is used to turn turbines. Wind energy is another where the force of the wind is used to turn giant, noisy and typically ugly 'wind turbines'. Solar power is another renewable energy resource where the sun's energy is converted to electric energy by solar cells.