Static Electricity - Electric Charge (Section 1)

Vocabulary flashcards covering key terms from the notes on electric charge, electrostatics, conductors, insulators, charge transfer, quantization, and conservation.

Electrostatics

The study of stationary electric charges and the forces between them.

Electric charge

A property of matter that comes in two types (positive and negative) and can be transferred between objects, causing forces.

Positive charge

A net positive charge that arises when an object loses electrons (more protons than electrons).

Negative charge

A net negative charge that arises when an object gains electrons (more electrons than protons).

Neutral

Having no net electric charge; the numbers of protons and electrons are equal.

Proton

A positively charged subatomic particle in the nucleus.

Electron

A negatively charged subatomic particle that can be transferred between objects.

Neutron

An electrically neutral subatomic particle in the nucleus.

Atom

The basic building block of matter; composed of protons, neutrons, and electrons; neutral when charges balance.

Coulomb

The SI unit of electric charge.

Elementary charge

The magnitude of the charge on a single electron or proton: 1.60×10−19 C.

Q

Symbol for electric charge (measured in coulombs).

Charge quantization

Electric charge occurs in integral multiples of the elementary charge; Q = N e.

One coulomb in elementary charges

One coulomb equals about 6.24×10^18 elementary charges.

Charging by friction

Charging objects by rubbing; electrons transfer between objects, creating separated charges (e.g., balloon gets negative, hair positive).

Charge transfer

Movement of electric charge from one object to another; can occur by contact or rubbing; total charge is conserved.

Conductor

Material that allows electric charges to move through it easily (e.g., copper, silver, gold, iron, graphite, plasma).

Insulator

Material that resists the flow of electric charges (e.g., plastic, glass, rubber, cloth, cotton, wood, dry air).

Conservation of charge

In an isolated system, total electric charge remains constant; charges can be transferred but not created or destroyed.

Like charges repel

Two positive or two negative charges repel each other.

Opposite charges attract

A positive and a negative charge attract each other.

Plasma

A state of matter consisting of free ions and electrons; conducts electricity; can form when air is ionized (e.g., lightning).

Neutral object becoming charged by rubbing

Rubbing transfers electrons, producing charged objects with separation of charges; no new charges are created.

Q = Ne

Relation: total charge Q equals number of elementary charges N times e, the elementary charge.

Air as conductor/insulator

Air is an insulator under normal conditions but can become a conductor when ionized (plasma).

Examples of conductors

Copper, silver, gold, iron, graphite, plasma.

Examples of insulators

Plastic, glass, rubber, cloth, cotton, wood, dry air.