Electric Energy at Home Chapter 6

Loss of Power What would happen if you had a power outage at your house? List all of the things that would be affected if you lost electricity to your home What would happen if you had a power outage in Airdrie?

Alberta Most of our energy comes from burning fossil fuels (coal, natural gas), to get electricity Potential chemical energy being converted into ________________

Michael Faraday investigated magnetic fields found that if you push a magnet through a coil of wire it creates an electric current More coils equals a stronger magnetic field These observations helped him create his first electric generator

Generating Electric Energy Section 6.1

generator made of a magnet and a coil of wire generators creating electricity to power buildings are huge kinetic energy  generator  electric energy input converter output

Generating and Distributing Electric Energy Section 6.2

Turbine Generator electricity is made in a generator which contains one or more turbines the turbines turn and their kinetic energy is transformed into electricity

Thermo-electric Power Plant common in Alberta coal is broken down into a powder it is burned, converting water into steam steam flows through pipes to spin a turbine turbine turns generator which creates electricity

Electricity from Water produces a lot of Canada’s electricity uses kinetic energy from falling water clean and efficient

Splitting Atoms for Energy Uranium atoms are split by nuclear fission this splitting releases a large amount of energy this thermal energy makes steam which turns a turbine

Distributing Electricity Downfalls to moving electricity great distances? can lose a lot of electricity to thermal energy as it is transferred to various areas through electrical lines Powerlines freeze with moisture, get knocked down and damaged

Electric Energy and Power Section 6.3

Energy and Work energy = the ability to do work Work (Joules) = Force (newtons) x distance (meters) W = Fd units = Joules (J)

Power Power = rate at which energy is transferred how fast energy is used or produced measured in Watts (W) 1W = 1J/s Power = Energy/time P = E/t

Example A generator produces 2 J of electric energy every second. How many watts of power does it produce?

Watt-hour (W•h) = measuring consumption of energy Energy = Power x time E = Pt kilowatt-hour (kW•h) = 1000 W•h

Examples How much electric energy does a 100 W light bulb use if it is left on for one hour? How much electric energy does a 240 W fan use if it is left on for two hours? A small kettle is rated at 1000 Watts. This means it uses 1000 W for each hour it is used. If it is used for 2 hours how much energy does it use in kilowatt hours?

Efficiency and Saving Energy Section 6.4

efficiency – measure of how completely input energy is converted to output energy how much input becomes output (how good is the machine in creating the proper energy) written as a percent %efficiency = (useful energy output/total energy input) x 100%

Examples An incandescent light bulb uses 30 000 J of electric energy. It emits only 900 J of useful energy. What is the efficiency of the light bulb?