Physics
A current flows through a metallic conductor for a long period of time. State the change you would expect in its:
(a) Resistance
(b) Resistivity
Answer
(a) As current flows for a long period of time, heat is generated and temperature increases. So, the resistance of metallic wire increases as resistance is directly proportional to the temperature of a conductor.
(b) As temperature increases, resistivity of metallic wire increases.
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