Schaums Easy Outline of Basic Electricity Revised by 
Electricity for Refrigeration, Heating, and Air Conditioning by 
V or E = Voltage defined as the electrical potential difference that causes electrons to flow.
I = Current defined as the flow of electrons and is measured in amperes.
R = Resistance defined as the opposition to the flow of electrons and is measured in ohms.
The Basics of Electricity
Matter: Made up of Atoms
Atoms: Smallest substance of matter. Made up of subatomic particles known as protons, neutrons, and electrons. The number of electrons in an atom is the same number of protons. Protons and Neutrons are located at the center of an atom known as the nucleus.
Neutrons have no charge
Protons have a positive charge
Electrons have a negative charge and orbit the nucleus in different shells that are at different distances from the nucleus. The number of electrons in each shell is determined by the number of electrons and the following formula: Number of Electrons=2s².
Atoms want to be stable so they either try to shed the outer electrons or fill their outer shell with electrons. When an atom is applied with force the electrons in the outer shell becomes free to move from Atom to Atom. When an atom has a surplus of electrons it has a negative charge when it has a deficiency of electrons it has a positive charge.
Electric Current is known as the Flow of Electrons.
Law of Charges states that like charges repel each other and unlike or opposite charges attract
Conductors: A path for electrical current to flow
Insulators: a material with several electrons in the outer orbit of the atom making them poor conductors of electricity (ex glass, rubber, plastic)
Ampacity:
Direct Current: electrical current moving in one direction
Alternating Current: electrical current that is continually reversing
Alternating and Direct Current
Voltage: the potential electrical difference for electron flow from one line to another in an electrical circuit
Magnetism: a force causing a magnetic field to attract ferrous metals, or where like poles of a magnet repel and unlike poles attract
Inductive Reactance: a resistance to the flow of an alternating current produced by an electromagnetic induction
Capacitive Reactance: a capacitor's resistance to electric current flow
Units of Electrical Measure:
is the instantaneous power, measured in watts (joules per second)
is the potential difference (or voltage drop) across the component, measured in volts
is the current through it, measured in amperes
Circuit: An electron or fluid-flow path that makes a complete loop
Components of an Electric Circuit:
Types of Circuits:
Parrallel
Series
Open
Closed
Short
Capacitive circuit
Inductive Circuit
Open Circuits, Closed Circuits & Short Circuits - Basic Introduction
Converter: an apparatus that changes DC to AC.
Rectifier: an apparatus found within a power supply or adapter that converts AC to DC.
Transformers: electrical devices the produce voltage in a second circuit through electromagnetic induction
Capacitor: a device in an electric circuit that stores electrical energy for later use
Resistors: resist, but do not totally block, the flow of electricity. They are used to control the flow of current.
Safety devices
Fuse: Prevents excessive current from passing through a circuit
Circuit Breaker: Switch that automatically interrupts or shuts off an electric circuit at the first indication of overload
Grounding: Completes an electric circuit and carries current safely away
is the instantaneous power, measured in watts (joules per second)
is the potential difference (or voltage drop) across the component, measured in volts
is the current through it, measured in amperes