Section 3.0

• Energy is the ability to do work

• Energy comes in many forms including:

1. Chemical Energy...gasoline, batteries, food

2. Electrical Energy...batteries, power stations, generators

3. Mechanical Energy...any object that has movement

4. Thermal Energy...fire or any type of heat

• These types of energy can be converted to other types as energy transformations. Ex. A Toaster converts electrical energy to Thermal energy.

• A Thermocouple a thermometer that converts thermal energy to electrical energy

• Electrical motor uses permanent magnets, electromagnets and a controlled flow of electricity to produce mechanical movement (movement may be used to turn the wheels in a remote control car etc)

• Direct current (DC) is a constant, never interrupted flow of electricity in a circuit.

• Alternating current (AC) is current that alternated directions or turns on and off 60 times every second

• AC is what is distributed to home and is available in wall sockets

• Many devices in our homes (such as TV, PS2, PS3) use DC and must have built in converters to change AC to DC

• Power is the rate at which a device converts energy and is measured in Watts... watts=current x volts [P = (I) x (V)]

• Energy consumption of any device can be calculated once you know the “Watts (P)” a device uses. [E = (P) x (t)]

• In our home we must pay for electricity used and power companies use the KWh or Kilowatts (1000 watts) we use in one hour. We calculate this by multiplying KW by Hours

1. 1 KW = 1000 W  Ex. 1200 W oven on for 2 hours = 1.2KW x (2) = 2.4 KWh

• Law of Conservation of Energy states that energy cannot be created or destroyed only changed/transformed

• Efficiency of a device is a measure of how much energy actually goes into performing the devices function (the rest is usually lost as heat energy)

• Efficiency = Joules of output divided by Joules of input x (100)

1. Ex. Light bulb uses input of 100J but only 5 J produce light (output) Efficiency = 5 / 100 = 0.05 x 100 = 5%

• No device is 100% efficient as friction causes energy loss in the form of thermal energy.

Section 4.0

• Fossil fuels, nuclear reactors, Hydro electric dams, Solar energy, Wind Energy, Hydrogen Fuel cells are all source of energy that we may use.

• Some source are Non-renewable (once we use them they are gone...fossil fuels)

• Some source are Renewable (they are constantly being replenished...Sunlight, Wind)

• Sustainability is the management of resources to they are there for future generations.

• Technology and technological advancements are reliant on electrical energy.

• Computers and Data Storage (binary code... 000110001111110)

• Electrical transmission of data (cell phone, wireless internet)

• Society as a whole is completely reliant on electricity to function at its current level.