science unit 2

Electricity

A way of transferring energy through wires as a flow of charges

Current (I)

The flow of electrical charge per second around a complete circuit, measured in amps (A) using an ammeter in series

Voltage / Potential Difference (V)

The energy transferred per unit charge between two points in a circuit, measured in volts (V) using a voltmeter in parallel

Resistance

A measure of how much a material opposes the flow of current, measured in ohms (

Ω

Ω)

Conductor

A material that allows electricity to flow through it easily (e.g., metals)

Insulator

A material that does not allow electricity to flow easily (e.g., plastics)

Cell

A chemical energy store that provides the push to move charge around a circuit

Battery

Two or more cells joined together

Series Circuit

A circuit with components connected in a single loop, giving only one path for current

Parallel Circuit

A circuit with multiple branches, providing more than one path for current

Electrode

A conductor in a battery; the negative electrode gives electrons, the positive electrode receives them

Electrolyte

A substance that allows ions to move between electrodes

Atom

The smallest particle of an element, made of protons, neutrons, and electrons

Electron

A negatively charged particle that moves around the nucleus and carries current

Proton

A positively charged particle found in the nucleus

Neutron

A neutral particle found in the nucleus

Ion

A charged particle formed when an atom gains or loses electrons

Energy

The ability to do work; it cannot be created or destroyed, only transferred between stores

Chemical Store

Energy stored in substances such as food, fuels, and batteries

Fossil Fuels

Non-renewable energy sources formed from ancient plants and animals (coal, oil, gas)

Non-renewable

Resources that take millions of years to form and will run out

Renewable

Resources that are naturally replenished and will not run out (e.g., solar, wind, hydroelectric)