Ohm's law

Ohms’s law was proposed by German physicist George Ohm and the law named after him. It is one of the basic equations used in the analysis of electrical circuits.

Definition:

Ohms law states that the current flowing in a circuit is directly proportional to the applied voltage and inversely proportional to the resistance across the circuit. Provided the temperature remains constant.

Mathematical representation:

I α V

⇒ I=V/R          (or)      V=IR

Where,I is the current passing through the circuit in amperes,

V is the voltage measured across the circuit in units of volts, and

R is the resistance across the circuit in ohms.

Ohms law assumes that R is a constant

Ohms law can also be defined as at constant temperature and conductivity of material, the current density is directly proportional to electric field intensity

J= σE where

Where, J is the current density,

E is the electric field, and

σ is a conductivity of the material.

Ohms law is not valid on all cases and can be applied only to linear circuits which have linear v-i characteristics.