Electrostatics Lecture Vocabulary

Vocabulary flashcards defining fundamental concepts, principles, and terms from the electrostatics unit.

Electrostatics

The study of electric charges at rest and the forces between them.

Coulomb's Law

The law stating that the force of attraction or repulsion between two charged bodies is directly proportional to the product of magnitude of charges and inversely proportional to the square of distance between them ($F = k \frac{q_1 q_2}{r^2}$).

Coulomb's Constant ($k$)

The constant of proportionality in Coulomb's law, given by $k = \frac{1}{4\pi \varepsilon_0}$, which equals $9 \times 10^9\,N\,m^2\,C^{-2}$ in SI units for a vacuum.

Permittivity of Free Space ($\varepsilon_0$)

A physical constant representing the capability of a vacuum to permit electric fields, equal to $8.85 \times 10^{-12}\,C^2\,N^{-1}\,m^{-2}$.

Point Charge

An imaginary charge located at a single point in space, such as an electron or an isolated spherical conductor viewed from an external point.

Superposition Principle of Force

The principle stating that when a number of separate charges act on a charge of interest, the resultant force is the vector sum of all individual electric forces computed separately.

Electric Field

The region around a charge in which a test charge can feel an electric force.

Electric Field Intensity ($E$)

The electric force per unit positive test charge at a given point in space ($E = \frac{F}{q}$), measured in newton per coulomb ($N\,C^{-1}$) or volt per metre ($V\,m^{-1}$).

Electric Field Lines

Imaginary lines drawn around a charged body to visually represent the direction and intensity of its electric field.

Electric Dipole

A charge configuration composed of two point charges of equal magnitude but opposite sign.

Fringing Field

The non-uniform, curved electric field pattern observed at the ends of oppositely charged parallel plates of finite length.

Potential Gradient

The rate of change of electric potential ($\Delta V$) with respect to displacement ($\Delta r$), defined mathematically as $\frac{\Delta V}{\Delta r}$.

Ferrofluid

A colloidal suspension of magnetic nanoparticles (usually iron oxide, $\text{Fe}_3\text{O}_4$) in a carrier liquid such as water or kerosene that becomes magnetized in the presence of a magnetic field.

Faraday Cage

A hollow conductor made of conducting material that distributes charge across its exterior surface to maintain a zero internal electric field, shielding its interior from external fields.