Electrostatic Potential and Capacitance Vocabulary

Vocabulary flashcards covering key terms, definitions, and concepts from Electrostatic Potential and Capacitance.

Conservative Force

A force (such as spring force, gravitational force, or Coulomb force) for which work done against it in moving a body between two points depends only on the initial and final positions, independent of the path taken.

Electrostatic Potential Energy Difference

The work required to be done by an external force in moving (without accelerating) a charge $q$ from one point to another in an electrostatic field, defined as $\Delta U = U_P - U_R = W_{RP}$.

Electrostatic Potential ($V$)

The work done per unit positive charge by an external force in bringing a unit positive charge (without acceleration) from infinity to a specific point in an electrostatic field.

Count Alessandro Volta

Italian physicist ($1745 - 1827$) who established that electricity generated in frog muscle tissue experiments was produced whenever a wet body was sandwiched between dissimilar metals, leading to his invention of the first voltaic pile (battery).

Electron Volt ($\text{eV}$)

A unit of energy equal to the energy gained by an electron ($q = e = 1.6 \times 10^{-19}\,\text{C}$) when accelerated through a potential difference of $1\,\text{V}$, equal to $1.6 \times 10^{-19}\,\text{J}$.

Equipotential Surface

A surface over which the electrostatic potential has a constant value at every point, making the electrostatic field normal to the surface at all points.

Electrostatic Shielding

The phenomenon in which the electric field inside a charge-free cavity of a conductor is always zero, protecting any interior region from external electric field influences.

Dielectric

A non-conducting substance with negligible mobile charge carriers that develops induced molecular dipole moments and an opposing internal electric field when exposed to an external electric field.

Polar Molecule

A molecule in which the centers of positive and negative charges do not coincide, resulting in a permanent (intrinsic) electric dipole moment even in the absence of an external electric field (e.g., $\text{HCl}$, $\text{H}_2\text{O}$).

Non-polar Molecule

A molecule in which the centers of positive and negative charges coincide, possessing no permanent electric dipole moment in the absence of an external field (e.g., $\text{O}_2$, $\text{H}_2$).

Polarisation ($\mathbf{P}$)

The net electric dipole moment per unit volume induced in a dielectric medium when placed in an external electric field.

Electric Susceptibility ($\chi_e$)

A dimensionless constant characteristic of a dielectric medium that relates its polarisation $\mathbf{P}$ to the electric field $\mathbf{E}$ via $\mathbf{P} = \varepsilon_0 \chi_e \mathbf{E}$.

Capacitor

A system composed of two conductors separated by an insulating medium, used to store electric charge and electrostatic potential energy.

Capacitance ($C$)

The ratio of the magnitude of charge $Q$ on either conductor of a capacitor to the potential difference $V$ between them ($C = \frac{Q}{V}$), measured in farads ($\text{F}$).

Dielectric Strength

The maximum electric field strength that a dielectric medium can withstand without experiencing dielectric breakdown and losing its insulating properties.

Dielectric Constant ($K$)

The dimensionless factor ($> 1$) by which the capacitance of a capacitor increases above its vacuum value when the space between its plates is completely filled with a dielectric medium ($K = \frac{C}{C_0} = \frac{\varepsilon}{\varepsilon_0}$).

Energy Density of Electric Field ($u$)

The electrostatic potential energy stored per unit volume of space in a region containing an electric field, expressed as $u = \frac{1}{2}\varepsilon_0 E^2$.

Fringing of the Field

The outward bending of electric field lines near the edges of finite parallel conductor plates, which causes slight field non-uniformity at the boundaries.