Electrostatics Lecture Notes

These flashcards cover the fundamental principles of electrostatics, including atomic structure, charge states, methods of electron transfer, and Coulomb's Law.

Electrostatics

The study of stationary charges or electrons at rest.

Electron ($e$)

A subatomic particle with a negative charge of $-1.6 \times 10^{-19}\,C$.

Proton ($p$)

A subatomic particle with a positive charge of $+1.6 \times 10^{-19}\,C$.

Neutron ($n$)

A subatomic particle that carries no charge.

Negatively charged object

An object in which the number of electrons is much greater than the number of protons (# \text{ of electrons} >> # \text{ of protons}).

Positively charged object

An object in which the number of electrons is less than the number of protons (# \text{ of electrons} < # \text{ of protons}).

Neutral object

An object in which the number of electrons equals the number of protons (# \text{ of electrons} = # \text{ of protons}).

Mass relationship ($m_p$ vs $m_e$)

The mass of a proton ($m_p$) is approximately 2000 times more than the mass of an electron ($m_e$).

Laws of Electrostatics

Like charges always repel, and unlike charges always attract; attraction may also happen between a charged and a neutral object.

Transfer by Rubbing (Friction)

A method of electron transfer that occurs when two different materials are rubbed together.

Transfer by Conduction

A method of electron transfer where a charged object comes into contact with an uncharged or neutral object.

Transfer by Induction

A method of electron transfer that occurs without contact when a charged object is brought close to an uncharged object.

Coulomb's Law

The magnitude of the electric force ($F_E$) that a particle exerts on another is directly proportional to the product of their charges ($q_1, q_2$) and inversely proportional to the square of the distance ($d^2$ or $r^2$) between them.

Coulomb Constant ($k$)

The constant of proportionality in Coulomb's Law, valued at $9 \times 10^9\,N \cdot m^2/C^2$.

Insulator

A material that differs from a conductor because it has fewer freely moving electrons.

Charge carriers in metal

Electrons are the charge carriers in metal rather than protons because they are smaller and loosely bound.