Energy Transfers + Resources

Flashcards covering key vocabulary and definitions related to energy transfers and resources, based on lecture notes.

Kinetic Energy Store

Moving objects have energy in their kinetic store.

Gravitational Potential Energy Store

Objects gain energy in their gravitational potential store when they are raised through a gravitational field.

Elastic Potential Energy Store

Objects have energy in their elastic potential store if they are squashed, stretched, or bent.

Electrostatic Energy Store

Objects with charge (like protons and electrons) have energy in their electrostatic store when they interact with one another.

Magnetic Energy Store

Magnetic materials interacting with one another have energy in their magnetic stores.

Chemical Energy Store

Chemical reactions transfer energy into or away from a substance's chemical store.

Nuclear Energy Store

Atomic nuclei release energy from their nuclear store during nuclear reactions.

Thermal Energy Store

All objects have energy in their thermal store; the hotter the object, the more energy it has in this store.

System (in Physics)

An object or group of objects.

Equilibrium (in a System)

When a system is in equilibrium, nothing changes and so nothing happens.

Mechanical Working

A force acts over a distance (e.g., pulling, pushing, stretching, squashing).

Electrical Working

A charge moves through a potential difference (e.g., current).

Heating (by particles)

Energy is transferred from a hotter object to a colder one (e.g., conduction).

Heating (by radiation)

Energy is transferred by electromagnetic radiation (e.g., visible light).

Oscillating Object

An object that moves back and forth in a regular rhythm.

Equilibrium Position (Pendulum)

The position at which the pendulum would hang undisturbed; considered to have zero gravitational potential energy.

Law of Conservation of Energy

Energy can be transferred usefully, stored, or dissipated, but cannot be created or destroyed.

Dissipated Energy

Unintended or wasted energy transfers, often resulting in the heating of objects and their surroundings.

Efficiency

The ratio of the useful power or energy output from a system to its total power or energy input.

Sankey Diagram

A diagram characterized by arrows that split to show the proportions of the energy transfers taking place in a system.

Fuels

A useful store of energy suitable for different purposes, selected based on ease of storage, energy content, and safety.

Fossil Fuels

Coal, oil, and natural gas, formed underground from the remains of plants and animals over millions of years.

Nuclear Fuels

Uranium-235 and plutonium-239, used in nuclear power stations.

Bio-fuels

Fuels made from plant matter, such as ethanol or methane.

Hydroelectric Dam

A dam that transfers energy mechanically from the gravitational potential energy store of water to its kinetic energy store to generate electricity.

Tidal Power

Uses underwater turbines placed between a river and the sea to generate electricity from the rise and fall of the tide.

Geothermal Energy

Energy derived from tectonic activity, where water is poured into shafts below the Earth's surface, heated by rocks, and returned as steam to turn a turbine.

Wind Power

The use of wind to turn a turbine and generate electricity, often implemented in wind farms.

Solar Cells

Also called photovoltaic cells, these transfer energy from sunlight electrically, producing a current and generating electricity.

Renewable Energy Resources

An energy source that is replenished at a faster rate than it is being used.

Non-Renewable Energy Resources

An energy source that is not replenished at a faster rate than it is being used and is therefore finite.