Electricity and Magnetism

static electricity

the accumulated charge on an object

electric force

the field force between two charged objects

electric field

a three dimensional region around a charged object that will apply a force on other charged objects within that region

electric potential energy

energy that is stored by a charged object in the electric field. The quantity depends on the magnitude of the charges and the object’s position in the field

charging by friction

the process by which an object can gain excess charge while being rubbed by another object

charging by conduction

the process by which one charged object can produce a second charged object by the two objects being placed in contact with each other and the excess charge being shared

charging by induction

the process by which one charged object can produce a second charged object by allowing the electric force to move excess charge onto the second object while the two objects are not in contact with each other

grounding

the act of providing a path for electrical charge to move into the earth

law of conservation of charge

the principle that states that charge cannot be created or destroyed but only transferred between objects

current electricity

electricity involving moving electric charges

electric current

the movement of electric charge through a complete loop

open circuit

an incomplete electric circuit that prevents the movement of charge

closed circuit

a complete electric circuit that allows charge to flow

direct current

electric current in which electric charges move only in one direction also known as DC.

conventional current

the direction in a DC circuit that positive charges would flow; decided by agreement as the standard current direction

alternating current

electric current in which the charge carriers change direction periodically

electrical conductor

a material through which electric charge moves easily

electrical insulator

a material through which electric charge does not move easily

semiconductor

a material with conductivity between those of conductors and insulators

ampere (A)

a fundamental SI unit of electric current

ammeter

a meter used to measure electric current though a circuit

voltage

the “force” that moves electric charge carriers through an electrical circuit; also called electric potential difference.

volt

derived SI unit for electrical potential difference equal to one joule per coulomb.

voltmeter

meter used to measure voltage

battery

a powers source for DC electrical device that slows down electric current of two or more electrochemical cells

resistor

an electrical device that slows down electric current by converting electrical energy into other forms, such as thermal energy

ohm

the derived SI unit for electrical resistance

electrical resistance (R)

an object’s opposition to the movement of charge carriers

superconductor

a material with zero resistance

Ohm’s Law

the law that states that the current in a circuit is directly related to the voltage and inversely related to the resistance

short circuit

an unintended path for an electric current

series circuit

a circuit with only on path that electric current can take

parallel circuit

a circuit with multiple paths that electric current can take

electric power

the work per second done or produced by electrical systems

fuse

an electrical safety device that opens the circuit by melting when an overheated condition occurs due to excessive current

circuit breaker

an electrical safety devices consisting of an automatic switch that opens when there is too much current in a circuit

electrical load

an electrical device in a circuit that consumes electrical energy