Electricity and Magnetism Flashcards

Flashcards based on lecture notes about Electricity and Magnetism.

Electric Charge (Q)

Measured in Coulombs (C). Charge on an electron is -1.6 x 10^-19 C, and on a proton is +1.6 x 10^-19 C. One coulomb contains 6.25 x 10^18 electrons.

Coulomb (C)

A unit of electric charge. If one coulomb of charge passes a point each second, one ampere of current is flowing.

Electric Current (I)

The flow of electrons in a wire, measured in amperes (A). It is the rate at which charge passes a point in a conductor.

Ammeter

A device used to measure current; it must be placed in series within the circuit for measurement.

Conventional Current

The movement of positive charges in a system, flowing from the positive terminal to the negative terminal.

Voltage (V) or Potential Difference

Energy per coulomb of charge, measured in Volts (V). It indicates the electric potential energy given to each coulomb of charge.

Voltmeter

A device used to measure voltage; it is connected in parallel across two points for measurement.

Resistance

A measure of how difficult it is for charge to move through a component, measured in Ohms.

Series Circuit

A circuit with components connected one after another, providing only one conducting pathway for current.

Parallel Circuit

A circuit with components side by side, providing multiple conducting pathways for current.

Magnetic field

A region in space where a magnetic substance experiences a non-contact force. The symbol for strength is B and the unit is tesla (T).

Solenoid

A coil of wire, sometimes with an iron core, that produces a magnetic field when current flows through it.

Right-hand grasp rule (Solenoid)

The fingers wrap around the coils of the solenoid in the direction of the current flow. The thumb points in the direction of the field inside the solenoid. The field outside the solenoid is in the opposite direction to that inside the solenoid.

Electromagnet

A solenoid with a magnetic field created by passing a current through it; the field collapses when the current stops.

Motor Effect

The force exerted on a current-carrying wire in a magnetic field, converting electrical energy into mechanical energy.

Lorentz Force

Another term for the motor effect and the magnetic force on a current-carrying wire.

Right Hand Slap Rule

A method determining the direction of the magnetic force when current flows, a magnetic force is exerted outwards on the wire The direction of the force is given by the Right Hand Slap Rule.

Armature

An electromagnet made by coiling thin wire around two or more poles of a metal core.

Commutator

A pair of plates attached to the axle providing connections for a coil of the electromagnet that work with brushes to let current flow to the electromagnet.