Question

Give two limitation of ohm law

Answer 1

The resistance of a material changes when the temperature changes. So when the resistance changes, the ratio of the voltage across the resistor and the current passing through it will not be a constant. We will not get the same numbers always. Non – linear elements and unilateral networks do not support ohm's law.

Answer 2

Answer:

The limitations of Ohm’s law are explained as follows:

*This law cannot be applied to unilateral networks.

A unilateral network has unilateral elements like diode, transistors, etc., which do not have same voltage current relation for both directions of current.

*Ohm’s law is also not applicable for non – linear elements.

Non-linear elements are those which do not have current exactly proportional to the applied voltage, that means the resistance value of those elements changes for different values of voltage and current. Examples of non – linear elements are thyristor, electric arc, etc.