Resistance, current, and potential difference are some of the core concepts of electrical circuits. If you’re building an electrical circuit, you’re going to need to know the circuit’s current, potential difference, and resistance to make sure everything works properly.

Ohm’s Law is a widely used mathematical formula to calculate the resistance equations. Read on as we detail what Ohm’s Law is and how you can use it to calculate the resistance equations.

What Is Electrical Resistance?

If you’re unfamiliar with resistance, then you should know that the resistance of an electrical circuit is often defined as the measure of the opposition to the flow of current. The unit of electrical resistance is ‘Ohms’ and is symbolized by the Greek letter “omega” (?).

What Is Ohm’s Law?

Ohm’s Law is a fundamental equation in electronics and essentially describes a mathematical relationship between the potential difference (voltage), current, and circuit resistance. The German physicist George Ohm was the first to verify this law experimentally.

Ohm’s Law states that the potential difference (voltage) across a conductor between two points is directly proportional to the current under constant resistance across the same two points. Mathematically, Ohm’s Law can be written as:

V = I * R

Where V is the potential difference (voltage) measured in Volts, I is the current flowing through the conductor measured in Amperes (A), and R is the resistance of the circuit measured in Ohms (?). You can use a multimeter to measure these quantities in an electrical circuit.

How to Calculate Resistance Equations Using Ohm’s Law

You can use Ohm’s Law equation to calculate the current, voltage, and resistance of a circuit. You can use the below formula triangle for calculating a specific quantity of an electrical circuit.

To calculate the current in a circuit, rearrange the Ohm’s Law equation as follows:

I = V / R

Similarly, you can calculate the electrical resistance of a circuit through:

R = V / I

Conditions Required For Ohm’s Law

For a circuit to obey Ohm’s Law, it is required that there be constant resistance. Electrical resistance in a circuit is affected by several physical factors, including temperature. The resistance of a material (such as copper wire) increases as the temperature increases, so Ohm’s Law does not hold true in that case.

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