Electromagnetism Glossary

ampere

A unit of electric current equal to a flow of one coulomb per second.

charge

The intrinsic electrical nature of a body. May be positive or negative.

dipole

Having opposite electric charge at opposite ends of a molecule or body.

electric current

The flow of electric charge, usually through a conductor or resistor. The term may refer to the flow of charged particles through a vacuum. In the context of current, charge may be electrons, ions or positive holes (in a semiconductor).

electric field

A region in which a stationary electric charge experiences a force due to the influence of another charged object.

electrical resistance

The ratio of the voltage across a component of a circuit to the current flowing through it: R = V/I. The Systems Internationale (SI) unit for electrical resistance is ohm (equivalent to a volt/ampere)

energy

The capacity of a physical system to do work. The capacity of electromagnetic radiation to do work

energy potential

The energy that an object possesses due to its position in a force field or that is stored in a system by virtue of the configuration and interaction between bodies in that system, e.g. elastic potential energy.

equipotential

Points in a field that have the same potential.

field

A region in which a body experiences a force due to the effects of another body. The effect can be the mass within the bodies, their charges or magnetic properties.

magnet

A magnetic material that has been magnetised, i.e. has a magnetic field.

magnetic material

A material that is capable of being magnetised

magnetised material

Magnetic material that has magnetic poles

non

ohmic

ohmic

Relating to a circuit element, whose electrical resistance obeys Ohm's Law.

resistor

An electrical component or material the properties of which limit the flow of an electric current through it.

solenoid

An electrical conductor that is wound into a helix with a small pitch, or into two or more coaxial helices, through which a current passes and establishes a magnetic field, usually to activate a metal bar within the helix and perform some mechanical task.

voltage

A measure of the electrical potential difference between two points. The SI unit for voltage is the volt (equivalent to joule/coulomb)

work (in physics)

Work done by a force when the application of that force results in movement having a component in the direction of the applied force.