| Term | Definition |
|---|---|
| attractive force | The electrostatic force exerted between two objects with opposite charges, pulling them together. |
| charge | A fundamental property of matter that causes objects to experience forces in electric fields; can be positive or negative. |
| charge carrier | Particles, typically electrons, that carry electric charge and constitute electric current in a conductor. |
| conductor | A material that allows electric charge to move through it, with resistivity that typically increases with temperature. |
| contact forces | Nonfundamental forces such as normal force, friction, and tension that result from the cumulative effect of many electric interactions between particles. |
| Coulomb's law | The law stating that the electrostatic force between two charged objects is directly proportional to the product of their charges and inversely proportional to the square of the distance between them. |
| electric force | The force exerted on a charged object by an electric field, equal to the product of the charge and the electric field strength. |
| electric permittivity | A measure of how easily an electric field can be established in a material. |
| electric polarization | The induced rearrangement of electrons by an external electric field, resulting in a separation of positive and negative charges within a material or medium. |
| electrically neutral | A state in which an object or system has equal amounts of positive and negative charge, resulting in no net electric charge. |
| electrostatic force | The force between charged objects at rest, described by Coulomb's law and dependent on the magnitudes and signs of the charges. |
| elementary charge | The magnitude of charge carried by a single electron or proton, denoted as e, representing the smallest indivisible unit of charge. |
| free space | A region of space with no matter, having a constant magnetic permeability value. |
| gravitational forces | Forces that result from the mass of objects and are always attractive in nature. |
| insulator | Materials that do not allow electric charge to move freely and can hold charge in fixed positions. |
| permittivity of free space | The electric permittivity of a vacuum, represented by the symbol ε₀, a fundamental constant. |
| point charge | An idealized model of a charged object treated as if all its charge is concentrated at a single location in space. |
| repulsive force | The electrostatic force exerted between two objects with charges of the same sign, pushing them apart. |
| Term | Definition |
|---|---|
| charge distribution | The spatial arrangement and density of electric charge in a region of space. |
| conservation of electric charge | The principle that the total electric charge in an isolated system remains constant over time. |
| contact | Direct physical touching between two systems that can result in the transfer of charge. |
| electron | Negatively charged particles that are the primary charge carriers in most common electrical circuits. |
| electrostatic force | The force between charged objects at rest, described by Coulomb's law and dependent on the magnitudes and signs of the charges. |
| friction | A process by which charge can be transferred between two objects through rubbing or contact. |
| grounding | The process of electrically connecting a charged object to a much larger neutral system, such as Earth, to neutralize its charge. |
| induced charge separation | The redistribution of charges within a neutral or charged system caused by the electrostatic force from a nearby charged object, resulting in polarization. |
| net charge | The total amount of electric charge in a system, accounting for both positive and negative charges. |
| polarization | The process by which a conductor's charge distribution shifts in response to an external electric field while maintaining equipotential conditions. |
| transfer of charge | The movement of electric charge from one system to another, typically involving the movement of electrons. |
| Term | Definition |
|---|---|
| charged conductor | Materials that allow electric charge to move freely throughout their structure and have accumulated electric charge. |
| charged object | An object that possesses electric charge and can experience forces from electric and magnetic fields. |
| electric field | A vector field that represents the force per unit charge exerted on a test charge at any point in space due to a charge distribution. |
| electric field line | A line in an electric field diagram whose direction at each point indicates the direction of the electric field, and whose density indicates the relative magnitude of the field. |
| electric field line diagram | A simplified model of an electric field map that uses lines to represent the magnitude and direction of the electric field at any position. |
| electric force | The force exerted on a charged object by an electric field, equal to the product of the charge and the electric field strength. |
| electrostatic equilibrium | A state in which excess charge carriers in a conductor have redistributed to the surface, resulting in no net charge in the interior and zero electric field within the conductor. |
| excess charge | The net charge that accumulates on or within a conductor or insulator beyond its neutral state. |
| insulator | Materials that do not allow electric charge to move freely and can hold charge in fixed positions. |
| isolated sphere | A charged spherical conductor that is far enough from other objects that their electric fields have negligible effects. |
| net electric field | The vector sum of individual electric fields created by multiple charged objects at a given location. |
| perpendicular to the surface | The orientation of the electric field at the surface of a charged conductor, forming a 90-degree angle with the surface. |
| point charge | An idealized model of a charged object treated as if all its charge is concentrated at a single location in space. |
| spherically symmetric charge distribution | A charge arrangement on a sphere where the charge is distributed uniformly in all directions from the center. |
| surface charge distribution | The arrangement of electric charge on the outer surface of a conductor in electrostatic equilibrium. |
| test charge | A point charge of small enough magnitude that its presence does not significantly affect the electric field it is used to measure. |
| vector field | A field in which each point in space is associated with a vector quantity, such as a magnetic field. |
| vector field map | A representation of a vector field showing the magnitude and direction of the field at various points in space. |
| Term | Definition |
|---|---|
| charge distribution | The spatial arrangement and density of electric charge in a region of space. |
| electric field | A vector field that represents the force per unit charge exerted on a test charge at any point in space due to a charge distribution. |
| integration | A calculus method used to sum infinitesimal contributions to find the total electric field from a continuous charge distribution. |
| principle of superposition | The principle that the total electric field is the vector sum of fields produced by individual charges. |
| symmetry | A property of charge distributions that allows simplification of electric field calculations by reducing the number of field components that need to be evaluated. |
| Term | Definition |
|---|---|
| area vector | A vector perpendicular to the plane of a surface with magnitude equal to the surface area, pointing outward from a closed surface. |
| closed surface | A surface that completely encloses a three-dimensional volume with no openings or boundaries. |
| dot product | A mathematical operation between two vectors that produces a scalar result, used to determine the component of one vector in the direction of another. |
| electric field | A vector field that represents the force per unit charge exerted on a test charge at any point in space due to a charge distribution. |
| electric flux | The measure of the electric field passing through a surface, calculated as the integral of the electric field dot product with the area vector. |
| surface integral | A mathematical integration performed over a two-dimensional surface to calculate the total effect of a vector field across that surface. |
| Term | Definition |
|---|---|
| charge density | The amount of electric charge per unit length, area, or volume of a charge distribution. |
| charge distribution | The spatial arrangement and density of electric charge in a region of space. |
| electric flux | The measure of the electric field passing through a surface, calculated as the integral of the electric field dot product with the area vector. |
| enclosed charge | The total electric charge contained within a Gaussian surface. |
| Gauss's law | A fundamental law of electromagnetism that relates the electric flux through a closed surface to the charge enclosed by that surface. |
| Gaussian surface | A three-dimensional, closed surface used in applying Gauss's law, typically chosen to have symmetry matching the charge distribution. |
| Maxwell's equations | A collection of four fundamental equations that fully describe electromagnetism and the behavior of electric and magnetic fields. |