In this reference sheet, presents a reference formula for fundamentals principles and rules in electric circuits.


Basic Properties

Voltage, resistance, and current are the three basic properties of electric circuits:

SI unit of voltage is volts

SI unit of resistance is ohms

SI unit of current is amps

How to Solve Resistors in Series

Two or more resistors are solved in series by simply adding them.

i.e R(eq) = R1 + R2 + … Rn

How to Solve Resistors in Parallel

Two or more resistors in parallel are solved using formula.


Learn more about parallel circuits

More Electrical Laws and Principles:

  1. Voltage Divider Rule
  2. Current Divider Rule
  3. Kirchhoff’s Current Law
  4. Kirchhoff’s’ Voltage law