Introduction: The creation of an electrical circuit requires the correct ratio of voltage to electric current used to product a circuit, a quantity known as resistance. This equation relating resistance to voltage and electric current, as shown below, is known as Ohm's Law. Ohm's Law can help electricians decide the resistance needed to create a circuit with a certain voltage and a certain amount of current.

Ohm's Law Equation: R=V/I, where R=resistance, V=voltage, and I=current

The SI unit for resistance is the ohm (`Omega`). The SI units for voltage and current are volts (V) and amperes (A), respectively. Therefore, 1 ohm is equivalent to 1 volt/ampere. Based on the equation for Ohm's Law, the resistance is directly proportional to the voltage and inversely proportional to the current. For example, if the voltage were to be doubled, the resistance would double, and the resistance would be halved if the current were doubled.

Resistance is an important concept when it comes to Ohm's Law and real-life applications of Ohm's Law, because it can help to limit the amount of current traveling through an electrical circuit. Resistors can be added in certain increments, and Ohm's Law helps to optimize this process.