A metallic conductor and a filament lamp are connected separately to the same DC…
PHYSICS · Multi-part · CBSE · Physics · Current Electricity · Current Electricity
Problem
A metallic conductor and a filament lamp are connected separately to the same DC source and their potential difference–current relationships are studied at room temperature.
(i) Define an ohmic conductor.
(ii) On the same set of axes, sketch the qualitative V–I curves expected for the metallic conductor and for the filament lamp. Label the curves clearly.
(iii) Explain, on the basis of temperature change in the conductor, why the metallic wire obeys Ohm’s law while the filament lamp does not under ordinary operating conditions.