Question

Ohm's law is valid________

Answer 1

Step 1: Ohm's law

1. Ohm's law states that the voltage across a resistance is proportional to the current flowing through the resistance when the temperature and other physical states are constant with time.
2. Ohm's law is defined by the form, $V=IR$, where, I is the current flowing through the resistance, R is the constant of proportionality and V is the voltage across the resistance.

Step 2: Voltage vs current graph

Step 3: Validation of ohm's law

1. According to Ohm's law, the voltage across the conductor is directly proportional to the current, i.e.$V\propto I$.
2. Al the conductor, those who obey Ohm's law are the ohmic conductor and others are the non-ohmic conductor.
3. If we plot a voltage vs current graph for any metallic conductor we will always get a straight line.
4. But, in the case of semiconductor (germanium, silicon) material, Ohm's law is not valid, we will get a different graph, which does not obey Ohm's law.

Therefore, Ohm's law is valid for all metallic conductors.