By increasing the temperature,the specific resistance (resistivity) of a conductor and a semiconductor,respectively,is:

As shown in the schematic below,a rod of uniform cross-sectional area $A$ and length $l$ is carrying a constant current $i$ through it and the voltage across the rod is measured using an ideal voltmeter. The rod is stretched by the application of a force $F$. Which of the following graphs would show the variation in the voltage across the rod as a function of the strain $\varepsilon$ when the strain is small? Neglect Joule heating.

If copper and silicon are cooled from $300 \, K$ to $60 \, K$,their resistivity will:

$A$ silver wire has a resistance of $2.1\; \Omega$ at $27.5^{\circ} C$ and a resistance of $2.7\; \Omega$ at $100^{\circ} C$. Determine the temperature coefficient of resistivity of silver.

The masses of three wires of copper are in the ratio of $1 : 3 : 5$ and their lengths are in the ratio $5 : 3 : 1.$ The ratio of their electrical resistances is

The resistance of the filament of an 'incandescent' bulb increases with an increase in temperature. If $R_{100}$,$R_{60}$,and $R_{40}$ are the resistances of $100 \ W$,$60 \ W$,and $40 \ W$ bulbs at room temperature,respectively,then: