In previous tutorial we understood the terms Voltage, Resistance and Current. In this tutorial we will understand relationship between these terms. The relation between them could be defined with Ohm’s Law. This law was given by the great scientist Georg Ohm. This law gives relation between V, I and R as follows: **V= I X R** **Voltage = Current X Resistance** WHAT IS THE USE OF THIS LAW? This law is helpful to find the values of the following parameter.

1. When you know Current and Resistance then you can easily find out voltage with below formula

**V= I X R** Let us continue with our simple circuit in earlier post. Put the values of I and R in above formula. Calculate the theoretical value.

2. Now let us assume you know the parameter voltage and resistance and you want to calculate current then use the following formula

**I = V / R** Calculate the theoretical value.

3. If you know Voltage and current and wanted to calculate resistance then use following formula.

**R = V / I** Do check the theoretical values. The simple way to remember these three formula is to remember the following pyramid. Remove the parameter which you want to calculate and look towards remaining part to get the formula.