Question
State Ohm's law. Write the necessary conditions for its validity. How is this law verified experimentally? What will be the nature of graph between potential difference and current for a
conductor? Name the physical quantity that can be obtained from this graph.

Answer

Ohm's law: The potential difference across the ends of a resistor is directly proportional to the current through it, provided it's temperature remains the same.
The conditions for its validity is temperature and all other parameters should be constant.
The nature of the graph is a straight line passing through the origin.
Resistance is the physical quantity that can be determined from the graph.

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