4.2 Electrical EnergyAashna Jain

Electrical energy

• It is the energy carried by moving electrons in an electric conductor.

• Electrons are forced down in a wire and the movement produces electricity.

• Electrons travel from one atom to another which makes the atoms imbalanced

Measurement

• Measured in Watts• Watts (LED- when turned on)• Watt-hours (Used for a longer time)• Kilowatts and Kilowatt-hours (Electricity bills)• Megawatts (electricity in an entire city)• Gig-watts (Large power plants)• US total electric capacity plants:1100 GW

Formula

• Energy transferred• Energy (J) = Power (W) x time (s)

• The power of a piece of electrical equipment depends on the voltage and current• Power (W) = Voltage (V) x current (A)

• Energy = Voltage x Current x Time

Uses

• Easy to transmit• Generated with AC or DC current• Lights• Air conditioners• Television• Computing• Water heating• Refrigeration

Examples

• Lightening (natural)• Too powerful to be confined in wires• Also an example of static electricity

• Dynamo, generator (Not natural)• Lamp (Light energy)• Heat in kettles, ovens etcetera (Heat energy)

Bibliography• http://ap-physics.david-s.org/electrical-energy/• http://www.ask.com/science/electric-energy-ddb91f717512643• http://shrinkthatfootprint.com/how-do-we-use-electricity• http://www.ucsusa.org/clean_energy/our-energy-choices/how-i

s-electricity-measured.html#.VQu4IUIxGHo

• http://www.wisegeek.com/what-is-electrical-energy.htm