Electricity Chapter 9

What Is Electricity? Electricity is a manufactured product. It is not something you pump out of the ground or mine or collect from the sun or wind. Electric power is manufactured from a rotating machine that we call an electrical generator. After it is generated, (manufactured) it is then delivered through copper wires to where it is used.

What is electricity? Electrical power is a form of energy. It is the flow of electrons. All matter is made up of atoms, and an atom has a center, called a nucleus. The nucleus contains positively charged particles called protons and uncharged particles called neutrons. The nucleus of an atom is surrounded by negatively charged particles called electrons. The negative charge of an electron is equal to the positive charge of a proton, and the number of electrons in an atom is usually equal to the number of protons. When the balancing force between protons and electrons is upset by an outside force, an atom may gain or lose an electron. When electrons are "lost" from an atom, the free movement of these electrons constitutes an electric current.

Electrons flow through a wire pushed by an electrical current, called the motive force.

Where do we get electricity from? We get power, which is a secondary energy source, from the conversion of other sources of energy, like coal, natural gas, oil, nuclear power and other natural sources, which are called primary sources. Before power generation began slightly over 100 years ago, houses were lit with kerosene lamps, food was cooled in iceboxes, and rooms were warmed by wood-burning or coal-burning stoves.

HOW IS POWER GENERATED? An electric generator is a device for converting mechanical energy into electrical energy. The process is based on the relationship between magnetism and power. When a wire or any other electrically conductive material moves across a magnetic field, an electric current occurs in the wire.

Industrial Generators An electric utility power station uses either a turbine, engine, water wheel, or other similar machine to drive an electric generator or a device that converts mechanical or chemical energy to power. Steam turbines, internal- combustion engines, gas combustion turbines, water turbines, and wind turbines are the most common methods to generate power.

Here the electrons only have one pathway to follow, each device will receive different amounts of voltage, the one light will be brighter than the second light.

Parallel Circuits allow the electrons more than one path to follow and the voltage is distributed evenly between devices.

HOW IS POWER MEASURED? Power is measured in units of power called watts. It was named to honor James Watt, the inventor of the steam engine. One watt is a very small amount of power. It would require nearly 750 watts to equal one horsepower. A kilowatt represents 1,000 watts. A kilowatt-hour (kWh) is equal to the energy of 1,000 watts working for one hour. The amount of power a power plant generates or a customer uses over a period of time is measured in kilowatt hours (kWh). Kilowatt hours are determined by multiplying the number of kW's required by the number of hours of use. For example, if you use a 40-watt light bulb 5 hours a day, you have used 200 watts of power, or.2 kilowatt hours of electrical energy..

Different Types Of Electrical Current Direct Current- This type of current comes from batteries and all of the electrons travel in just one direction. Alternating Current- This is the current that comes from the wall, the electrons can alternate, or change the direction in which they move.

Amps, Volts, Watts The ampere (symbol: A) is the SI unit of electric current. [1] The ampere, in practice often shortened to ampSIelectric current [1] The volt (symbol: V) is the SI derived unit of electromotive force, commonly called "voltage". [SIderived unit electromotive forcevoltage [ The watt (symbol: W) is a derived unit of power in the International System of Units (SI). It measures rate of energy conversion. One watt is equivalent to 1 joule (J) of energy per second.derived unitpowerInternational System of Unitsjouleenergysecond

Ohms Law Ohm’s Law illustrates the relationship between watts, volts and amperes and in a mathematical equation. I = V/R Where I stands for Amps, V stands for Volts and R stands for resistance.