Potential difference flowing through a conductor is directly proportional to the electric current when the temperature and other physical properties are kept constant.
\(V = I\times R\)
If Ohm's law is obeyed, the graph against it or otherwise is a straight line as follows:
Conductor which obeys Ohm's Law (Resistance constant)
Example: Constantan wire
Conductor which does not obeys Ohm's Law (Resistance constant)
Example: Filament bulb
Factors that affect the resistance of a wire
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