Kinetic and Potential Energy

• Energy makes things happen.
• Energy is not matter, but acts upon matter.
• Energy compels matter to perform actions.

Types of Energy

• Energy is classified into kinetic and potential forms.
  • Kinetic: Mechanical, Sound, Electrical, Thermal, Light.
  • Potential: Chemical, Nuclear, Gravitational, Elastic.

Law of Conservation of Energy

• Energy cannot be created or destroyed.
• Energy can be converted from one form to another.
• Energy can be transferred from one object to another.
• The total energy in the universe is constant.
• Transformation of energy involves changing energy from one form to another.
• Transfer of energy involves moving energy from one place to another, possibly without transformation.

Energy Efficiency

• Useful energy is the energy that is needed.
• Waste energy is the energy that is not needed.
• Energy efficiency occurs when an object's input is predominantly high in useful energy rather than waste energy.
• Energy efficiency is calculated as (Useful energy output / Total energy output) x 100%.

Sankey Diagrams

• Sankey Diagrams represent energy transformations.
• They visually convey the amount of inputted energy and the amount of output energy converted into different types.
• A higher proportion of useful energy output indicates energy efficiency.
• A higher proportion of useless energy output indicates waste energy.
• The thickness of arrows represents the amount of energy involved.

Increasing Energy Efficiency

• Streamlined shapes, lubrication, and thermal insulators increase energy efficiency.

Sources of Energy

• Electrical generators must spin a metal coil around a magnet to start the flow of electrons through the metal – creating electricity.
• All electricity production using a generator requires an input of some form of energy to make the coil spin.

Coal

• Coal is a significant source of electricity in Australia.
• Coal is made of ancient plant remnants compacted over millions of years.
• Coal is a near-pure form of carbon.
• Coal contains chemical energy between chemical bonds.
• Chemical bonds are flammable/combustible.
• Burning coal heats water to produce steam.
• High-pressure steam forces a turbine to spin a coil in a generator, starting the movement of electrons in wires, and creating electricity.
• Burning of coal generates carbon dioxide which is released to the atmosphere.

Renewability and Sustainability

• Renewability is the term to describe how quickly resources form.
  • Non-renewable resources: Form over very long periods and have a fixed amount like coal, oil, natural gas, nuclear energy.
  • Renewable resources: Regenerate quickly and have an infinite supply like solar, hydro-electrical, geothermal, tidal, wind, biomass.
• Sustainability depends on the ability to continue indefinitely, where resources are not used up faster than generated.

Electricity

• Matter is made up of atoms.
• Electrons possess a negative charge and can move between atoms.
• The movement of electrons creates an imbalance of charge-static electricity/stationary electricity.
• Protons possess a positive charge.
• Like-charged objects repel while opposite charges attract.
• Electricity is a constant flow of electrons from one atom to the next.

Conductors vs. Insulators

• Conductors have loosely bound electrons that can be passed between atoms, allowing electricity to flow.
• Insulators have tightly bound electrons that cannot be passed between atoms, not allowing electricity to flow.

Circuits

• Consist of:
  • A power source
  • A conductor connecting all the components
  • A device which uses the electrical charge
  • A switch to connect or break the circuit (optional)

Voltage

• Voltage represents the difference in potential energy between two points in a circuit.
• Voltage describes how much energy each charge contains.
• Voltage is the attraction or push of electrons across the circuit.
• Potential is measured in volts (V) with a voltmeter.
• Voltage is measure of the (potential) difference in energy between the electrons entering and leaving the circuit at the power source.
• The difference in energy between electrons is the attraction or the push of electrons across the circuit.
• Voltage is the cause of a current.
• A voltmeter is always placed in a parallel circuit to measure the 'push' across the light bulb.
• Voltage does not remain consistent throughout the circuit.

Current

• Current measures how fast charge moves in a circuit (how many electrons are flowing through the circuit per second).
• Current is the effect of voltage.
• Current is measured in amps (A).
• Currents can move in either direction through the position of charge.
• Ammeters are always placed in series circuits to measure the flow within the circuit.