1. ALTERNATING CURRENT- THE CURRENT SWITCHES DIRECTION BACK AND FORTH. Used in generators, motors, and power distribution centers 2.Direct current- electricity flows in a constant direction. Used in batteries. There is a positive and a negative terminal 3.Resistance- the property of a conductor in which the passage of a current causes electric energy to be transformed into heat. Measured in ohms. You want low resistance in electrical wiring! 4.Capacitor- device for accumulating and holding a charge of electricity 5.Frequency- the number of cycles or completed alternations in a given unit of time (how many times it turns)

1.Turbine- a machine with a rotor (blades) that are driven by pressure or momentum (such as water pushing them around) 2.Circuit-the complete path of an electric current, including the generating apparatus, resistors, capacitors, and the load 3.Motor-converts electrical energy into motion (ex. The fan motor makes the fan turn around) 4.Generator- converts motion energy into electricity (ex. Generators are found inside power plants, or are gas powered that can power your appliances in a power outage situation) 5.Transformer- increase OR decrease the voltage of electricity

1.Ground- a conducting connection between an electric circuit or equipment to the earth OR some other conducting body. It turns out that the power company uses the Earth as one of the wires in the power system. The planet is a good conductor, and it's huge, so it makes a handy return path for electrons. "Ground" in the power- distribution grid is literally the ground that's all around you when you are walking outside. It is the dirt, rocks, groundwater and so on. The bare wire running down the power pole runs directly to the earth. Earth 2.Step up transformer- Increases the voltage in order to travel long distances over transmission power lines 3.Step down transformer- decreases voltage from 350,000 to 12,000 volts in preparation to go into the home

1.Transmission line- interconnected lines that electricity travels on from the power stations as it makes it way to homes 2.Distribution lines- overhead OR underground lines that carry electricity to the homes 3.Substation- small fenced in building that contains transformers, switches, and other electrical equipment 4.Voltage- the force of an electric charge. The higher, the more charge 5.Renewable energy- Any naturally occurring source of energy (example: water) 6.Nonrenewable energy- energy source that has a limited supply (example: fossil fuels, nuclear fuels)

1.Watt- Unit of electrical power. Appliances require a certain number of watts to work correctly 2.Kilowatt-hour- measures the amount of electricity used in one hour. (this is how we pay for the electricity we use in homes and businesses) 3.Efficiency- the ratio of work done to the energy supplied to it (think high effieciency washers. They are efficient in washing our clothes with little water)

1.Greenhouse gases- any of the gases whose absorption of solar radiation is responsible for the greenhouse effect (warming) This includes CO2, ozone, CFCS, methane 2.Global warming- The increase in the earths average atmosphere temperature that causes changes in climate 3.Recycling- to treat or process used materials so as to make suitable for re-use 4.Deforestation- to clear off (cut) forests or trees