Ohms law is very important and basic laws that used in an electrical system. It shows the linear relationship between voltage, current and Resistance. Ohms law was discovered by a great scientist known as Georg Simon Ohm. According to the ohms law the current flowing through the electric circuit is directly proportional to the potential difference across the circuit and inversely proportional to the resistance of the circuit, provided the temperature remains constant. The ohms law can be defined by the formula given as:-
V=IR (Here R is constant)
Lets understand the equation:-
Here V=voltage to be measured across the conductor in unit volt (V)
I=current flowing in the conductor in the unit ampere (A)
R=resistance of the conductor in unit ohms (Ω)
e.g in a circuit 5A of current flow and has a resistance of 1ohm. Find out the voltage in the circuit
solution- in the question current and resistance is known so we can find the voltage as given formula
hence we can find the voltage with the help of ohms law if any two of these is known.
We can also find current and resistance respectively
The ratio of potential difference(V) between any two points of a conductor to the current flowing between them is constant provided that the temperature of the conductor remains constant.
Ohms law can be applied either to the entire circuit or to the part of the circuit.
Limitation of ohm’s law
It is not applicable to the non-linear devices such as diodes, zener diodes, voltage regulations etc.
It does not hold good for non-metallic conductors such as silicon carbide. The law for such conductors is given by
Where K, m are constant.