Select the correct statement.

Write the limitations of Ohm's law.

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

For a wire,$\frac{R}{l} = \frac{1}{2} \, \Omega/cm$ and the length of the wire is $l = 5 \, cm$. If a potential difference of $1 \, V$ is applied across it,the current through the wire will be: $(R = \text{Resistance})$ (in $A$)

The $V-I$ graphs $A$ and $B$ are drawn for two voltameters. Identify each graph.

Of the following graphs,the one that correctly represents the $I-V$ characteristics of an 'Ohmic device' is: