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. $T_1< T _2$
• C. $T_1=T_2$
• D. $T_1=2 T_2$

Answer 1

Answer: (A)

Slope of graph will give us reciprocal of resistance.
$\left(\text { as } \frac{i}{V}=\frac{1}{R}\right)$
Here resistance at temperature $T_1$ is greater than that at $T_2$
Since resistance of metallic wire is higher at higher temperature than at lower temperature, hence $T_1>T_2$.