01/05/23

Energy and ElectricityEnergy and Electricity

01/05/23The 9 types of energyThe 9 types of energyType 3 example sourcesHeat

Kinetic (movement)NuclearSoundLight

ChemicalElectrical

Gravitational potentialElastic potential

Type 3 example sources

01/05/23Energy changesEnergy changesTo describe an energy change for a light bulb we need to do 3 steps:

Electricity Light + heat

1) Write down the starting energy:

3) Write down what energy types are given out:

2) Draw an arrow

What are the energy changes for the following…?1) An electric fire2) A rock about to drop3) An arrow about to be fired

01/05/23Electrical EnergyElectrical EnergyConsider a simple circuit:

Words – electrical (x2), light, chemical

The job of the battery is to convert ______ energy into _________ energy…

The job of the bulb is to convert the _________ energy it receives from the battery into ______ energy.

01/05/23Electrical EnergyElectrical Energy

Energy

Hi. I’m Ernie Electron and I’m

going to show you how I get energy around a circuit.

01/05/23Electrical EnergyElectrical Energy

Energy

Hi. I’m Ernie Electron and I’m

going to show you how I get energy around a circuit.

01/05/23Electrical EnergyElectrical EnergyHi. I’m Ernie Electron and I’m

going to show you how I get energy around a circuit.

Energy

01/05/23FuelsFuelsA “fuel” is something that can be burned to release heat and light energy. The main examples are:

Coal, oil and gas are called “fossil fuels”. In other words, they were made from fossils.

01/05/23Renewable energy sourcesRenewable energy sourcesWind

Tidal

Hydro-electric

Geothermal

Biomass

Wave

01/05/23Power stationsPower stations

Cooling tower

Turbine

Generator

Transformer

Boiler

01/05/23What does What does each part each part

do?do?

The boiler is where the fuel is burnt to boil water

The steam from the boiler is used to turn a turbine

The turbine is connected to the generator, which acts like a dynamo – it generates electricity out of movement

The steam is cooled down and turned back into water in the cooling tower

01/05/23Energy Transfer diagramsEnergy Transfer diagramsConsider a light bulb. Let’s say that the bulb runs on 100 watts (100 joules per second) and transfers 20 joules per second into light and the rest into heat. Draw this as a diagram:

100 J/s electrical energy

“Input” energy “Output” energy

80 J/s heat energy (given to

the surroundings)

20 J/s light energy

01/05/23Example questionsExample questionsConsider a kettle:

1) Work out each energy value.

2) What is the kettle’s efficiency?

Sound energy

Wasted heat

Heat to water

2000 J/s electrical energy

Consider a computer:

150 J/s electrical energy

10 J/s wasted sound

20 J/s wasted heat

Useful light and sound

1) How much energy is converted into useful energy?

2) What is the computer’s efficiency?