how is electricity generated? when a magnetic field is in motion relative to a copper wire, it...

ELECTRICITYLINDSAY BRENNAN

KRISTINA TRASE

How is Electricity Generated?

When a magnetic field is in motion relative to a copper wire, it triggers the flow of electrons in

the wire, creating electricity.

Electricity Timeline 1752

Benjamin Franklin invented the lightening rod - he demonstrated lightning was electricity.

1786Italian physician, Luigi Galvani demonstrated what we now understand to be the electrical basis of nerve impulses when he made frog muscles twitch by jolting them with a spark from an electrostatic machine.

1800First electric battery invented by Alessandro Volta. Volta proved that electricity could travel over wires.

1820 Relationship of electricity and magnetism confirmed by

Hans Christian Oersted who observed that electrical currents effected the needle on a compass and Marie Ampere, who discovered that a coil of wires acted like a magnet when a current is passed thorough it.

1821 First electric motor invented by Michael Faraday.

1826Ohms Law written by Georg Simon Ohm states that

"conduction law that relates potential, current, and circuit resistance"

1831Principles of electromagnetism induction, generation and transmission discovered by Michael Faraday.

1879 Edison demonstrates his incandescent lamp, Menlo Park, New Jersey.

1886The Westinghouse Electric Company is organized. 40 to 50 water powered electric plants reported on line or under construction in the U.S. and Canada.

Direct current electricity flows in one direction all the time. Electricity using batteries is DC electricity. The poles of a battery always stay the same.

AC electricity is also known as alternating current. The electrical source switches (alternates) polarity many times a second. AC electricity is what comes out of your outlets at home.

AC/DC CURRENT

DC CURRENT

AC CURRENT

NEVER PLAY WITH POWER OUTLETS!!

The steady flow of electricity is called an electric current. A current will move along a wire or a path called a circuit. Amps are used to measure how much electric current is moving through a wire.

Circuit means to “go around.”

• Has a single loop for electrons to travel round• Components are connected one after another• Current is the same at all points• Voltage is shared between components

• Has two or more paths for electrons to flow down

• Current is shared between the branches• Sum of the current in each branch = total current• Voltage loss is the same across components

Parallel

Series

• Lights in our homes are wired in parallel circuits.

Wire

Cell/Battery

Light

On/off switch

Resistor

Voltmeter

Ohmmeter

Parallel Circuit

Series Circuit

Current measured in amps (A)Voltage (V) – Increase or decrease in the amount of electrical energy carried by the current.

Equations

KEY:o P= Powero E= Voltageo I= Currento R= Resistance

Wind Power

Hydropower

Geothermal Power

Solar Power

Biomass Energy

Wind power, hydropower, and geothermal energy work basically the same way. A movement in the environment

causes a turbine to spin which spins a generator. The generator converts the mechanical energy to electrical

energy.

Wind turbines can be found all over the US but the most productive states are

Texas, Iowa, California, and Washington.

• Moving water turns a turbine.

• Hydropower plants are found in places with dams or waterfalls.

• It accounted for 6% of total U.S. electricity generation and 67% of generation from renewables in 2008.

Geothermal energy can be found where hot spots are located in the earth.

Geothermal energy is heat from within the Earth. We can recover this heat as steam or hot water and use it to heat buildings or generate electricity.

Geothermal energy is a renewable energy source because the heat is continuously produced inside the Earth.

Solar energy can be converted to electricity in two ways: Photovoltaic cells (or solar cells) and Concentrating Solar Power Plants

Photovoltaic cells change sunlight directly into electricity while concentrating cells generate electricity by using the heat from solar thermal collectors to heat a fluid which produces steam that is used to power the generator.

When woods, crops, manure,

and some garbage are burned, the

chemical energy in biomass is

released as heat. These things can be burned to also

produce steam which can generate

electricity.

HOW THE U.S. GENERATES ELECTRICITY

Country Average KWH

United States 3,920,613,000,000

China 2,054,568,000,000

Japan 1,031,262,000,000

Canada 548,794,000,000

Mexico 187,617,000,000

Haiti 256,000,000

5% (USA population) of the world’s population consumes 23% of its energy!

Comparison of EnergyConsumption

What is Energy Star?ENERGY STAR is a joint program of the U.S.

Environmental Protection Agency and the U.S. Department of Energy helping us all save money and protect the environment through energy efficient products and

practices.

http://buckeyephysics.pbworks.com/kristina-and-lindsay-presentation