Static Electricity and Electric Charge

Vocabulary and key concepts regarding static electricity, atomic structure, and the mathematical relationship between charge and current.

Statically charged

The state of an object, such as a PVC pipe rubbed with a woollen cloth, that allows it to attract other objects like paper shreds or dust.

Neutral (electrically)

The state of an uncharged object that contains exactly the same amount of positive charge and negative charge.

Electrons

Small, negatively charged particles that travel between a cloth and an object during rubbing, resulting in an electric charge.

Positive charge (rubbing)

The charge acquired by a Perspex rod when it is rubbed with a silk cloth.

Negative charge (rubbing)

The charge acquired by a PVC tube when it is rubbed with a woollen cloth.

Law of attraction and repulsion

Objects with the same charge repel each other, while objects with different charges (plus and minus) attract each other.

Protons

Positively charged particles located in the nucleus of an atom that cannot move from their position in a solid.

Voltage

The condition that exists between two differently charged objects, such as a negatively charged ball and a positively charged ball.

Electric current

The movement of electrons that occurs when a conducting connection is made between two objects with a voltage between them.

Coulomb ($C$)

The unit of electrical charge, named after Charles-Augustin Coulomb, equal to the charge of $6.2 \times 10^{18}$ electrons.

Formula for Charge ($Q$)

$Q = I \times t$, where $Q$ is the charge in coulombs ($C$), $I$ is the current in amps ($A$), and $t$ is the time in seconds ($s$).

Elementary charge

The smallest amount of charge found in nature, valued at $1.6 \times 10^{-19}\,C$, which is negative for electrons and positive for protons.

Free electrons

The outermost electrons in metal atoms that can easily move from one atom to the next, allowing current to flow.

Conductors

Materials, such as metals, that have free electrons and allow electric current to pass through them.

Insulators

Materials that do not have free electrons and therefore cannot conduct electric current.

Neutrons

Particles that, along with protons, make up the positively charged nucleus of an atom.