State and explain Ohm’s law.
Ans: Ohm’s law: As long as physical conditions (such as dimensions, pressure and temperature) are constant, the potential difference or voltage applied across the conductor is directly proportional to current flowing through it.
OR
As long as physical conditions (such as dimensions, pressure and temperature) are constant, the current flowing through the conductor is directly proportional to the potential difference or voltage applied across it. V ∝ I Or I ∝ V i. e. V = R I Or I = V/R where, R = constant of proportionality, called as the resistance of the conductor.