Question

Ohm's law is valid only under which condition regarding physical conditions?

Options

• The current must vary over a wide range

• Physical conditions must remain unchanged

• Physical conditions must change continuously

• The temperature must increase steadily

Answer 1

Ohm's law is valid only when physical conditions remain unchanged. If temperature changes, resistance may change, and if the internal structure or material response changes with current, linearity is lost, causing practical devices to depart from ideal ohmic behaviour.