With our **Ohm's Law Calculator** you can calculate any of the unknowns involved in it as long as you know the value of the other two unknowns. Know the value of the resistance, voltage or current of the circuit you want:

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## Definition Ohm's Law

The** Ohm's Law** is one of the pillars of the world of electricity and electronics and thanks to it we know that:

The intensity of the electric current (I) flowing through an electrical conductor is directly proportional to the applied potential difference (V) and inversely proportional to its resistance (R).

This potential difference mentioned in the definition of Ohm's Law is the main reason that causes the **movement of electric charges through a conductor**.

## Ohm's Law Formulas

To understand a little more **how Ohm's Law works**In this section, we are going to see which are the different formulas that we can use depending on the variable we want to calculate:

Voltage = Current x Resistance

Current = Voltage / Resistance

Resistance = Voltage / Current

These are the **three formulas of Ohm's Law.** If you don't remember any of them, there is a trick that consists of drawing a triangle like the one above these lines. Now place the letters VIR as they appear in the picture and draw a line just above the letters IR.

To remove the **formulas of Ohm's Law with this mnemonic rule** just cover with your finger the letter of the variable you want to calculate and the formula will automatically appear in the triangle. Do the test and cover the I, you will see that you get V/R. Like this with the rest of the variables.

Another important aspect of the formulas are the **measurement units**. Remember that voltage is measured in Volts (V), current in Amperes (A) and resistance in Ohms (Ω).

## Ohm's Law Exercises

### Example 1

We are going to invent a** Ohm's Law practical exercise** in which we will calculate the current that passes through a wire if we have a 220V source and a resistance of 1200 Ω.

We resort to the formula given by the** intensity value** and we have that:

I = V/R = 220V / 1200Ω = 0.183A.

### Example 2

We are asked to** calculate the resistance** in a circuit fed by a 50V source through which a current of 2 Amperes flows.

R= V/I = 50V / 2A = 25Ω

### Example 3

To cover the other variable of Ohm's Law exercises, we now go to **calculate the voltage of a circuit** which has a resistance of 20Ω and through which a current of 3A flows:

V = I x R = 3A x 20Ω = 60 Volts

If you have any questions about Ohm's Law leave us a comment and we will help you.

I like the ohm calculator

I liked the exercises...they were very clear for me, thank you.

Thank you Agustín, we are glad to know that our explanation of Ohm's Law has been useful to reinforce your knowledge. We hope to see you here more often.