Electricity

Electricity is the form of energy (the ability to do work) that results from charged particles (electrons, protons). Power ($P$) from electricity is generated when potential electrical energy, referred to as voltage, is released so that it "flows" through a conductor as a current where it encounters resistance. This flow is mathematically described by Ohm's Law, and the amount of power generated is described by the Watt's Law.

Relationships between Voltage, Current, Resistance, and Watts

Ohm's Law and Watt's Law describe the relationship between volts, amps, ohms and watts as $I = V/R$ and $P=IV$, respectively. These equations allow for substitutions: for example $I$ can be substituted with $V/R$ so that $P=(V/R)V$ or $P=V^2/R$.

SI Units Used in Electricity

NameSymbolMeasuresDefinition
Ampere$A$Current${C}/{s}$
Coulomb$C$Charge$A \cdot S$
Farad$F$Capacitance$C/V$
Henry$H$Inductance$Wb/A$
Hertz$Hz$Frequency$s^{-1}$
Ohm$\Omega$Resistance$V/A$
Siemens$S$Conductance$A/V$
Tesla$T$Magnetic field strength$Wb/m^2$
Volt$V$Voltage$W/A$
Watt$W$Power$J/s$
Weber$Wb$Magnetic flux$V \cdot s$

Deeper Knowledge on Electricity

Charge and Coulombs

How force is exerted in electromagnetic field, measured in coulombs

Conductance and Siemens

The ability to conduct to current, measured in siemens

Current and Amperes

The flow of electricity, measured in amps

Electrical Engineering

Build and deconstruct electrically powered devices

Ohm's Law

A formula for determining voltage, current, and resistance

Resistance and Ohms

Opposition to current, measured in ohms

Voltage and Volts

Electrical potential energy, measured in volts

Watt's Law (Power Law)

A formula to define the relationship between power, voltage, and current (P=IV)

Broader Topics Related to Electricity

Physics

The fundamental nature and properties of matter, energy, and motion

Power (Physics)

Energy that results from charged particles