Question

The current i and voltage $V$ graphs for a given metallic wire at two different temperatures $T_1$ and $T_2$ are shown in the figure. It is concluded that

• A. $T_1 > T_2$
• B. $T_2 < T_2$
• C. $T_1 = T_2$
• D. $T_1 = 2T_2$

Answer 1

Answer: (A)

Slope of graph will give us reciprocal of resistance.
$\left(a s \frac{1}{V}=\frac{1}{R}\right)$
Here resistance at temperature $T_{1}$ is greater than that at $T_{2}$
Since resistance of metallic wire is max at higher temperature then at lower temperature, hence $T_{1}>T_{2}$