Question

Which of these relation holds good for an Ohmic conductor?

(a) V-I relationship is non-linear

(b) The straight-line V-I graph pass through the origin

(c) V-I relationship is non-unique

(d) V-I relationship depends on the sign of V for the same absolute value of V

I got this question during an online interview.

The doubt is from Current Electricity topic in section Current Electricity of Physics – Class 12

Answer 1

Correct option is (b) The straight-line V-I graph pass through the origin

To explain: The conductors which obey Ohm’s law are called Ohmic conductors. The linear relationship between voltage and current for these conductors hold good. The resistance (R=\(\frac {V}{I}\)) is independent of the current through the conductor. The magnitude of current changes linearly with voltage. Hence the V-I graph for ohmic conductors is a straight line passing through the origin.