• Electromotive Potential

  Measured in Volts, is represented by the letter V (or E)

• Current

  Measured in Amperes, is represented with the letter I

• Resistance

  Measured in Ohms, is represented by the letter R (or the Greek letter Ω)

• Power

  Measured in watts, is represented by the letter W

• Glossary of Terms

States the relationship between voltage, current and resistance. Given the relationship between these three elements, once you know any two of them, it is possible to calculate the third.

• V = IR

  Volts = Amps x Ohms

• I = ^V/_R

  Amps = Volts / Ohms

• R = ^V/_I

  Ohms = Volts / Amps

Watt's Law is similarly useful in figuring out the relationship between power, voltage and current.

• W = VI

  Watts = Volts x Amps

• V = ^W/_I

  Volts = Watts / Amps

• A = ^W/_V

  Amps = Watts / Volts