Finding a resistance is very easy all you have to do is only putting a particular type of resistors into it. What is resistance of the any given material? Resistance is the ability to stop down the flow of current through them. Which Theory used to find the resistance? Wheatstone bridge is used to find the resistance. What is Wheatstone bridge?  Wheatstone bridge is an electrical circuit used to measure an unknown electrical resistance by balancing two legs of a bridge circuit, one leg of which includes the unknown component. Its operation is similar to the original potentiometer. It was invented by Samuel Hunter Christie in 1833 and improved and popularized by Sir Charles Wheatstone in 1843. One of the Wheatstone bridge’s initial uses was for the purpose of soils analysis and comparison.