The reciprocal of resistance is

$A$ metal rod of length $10 \ cm$ and a rectangular cross-section of $1 \ cm \times 0.5 \ cm$ is connected to a battery across opposite faces. The resistance will be . . . . . . .

What is conductance? Write its unit.

Masses of $3$ wires of same metal are in the ratio $1 : 2 : 3$ and their lengths are in the ratio $3 : 2 : 1$. The electrical resistances are in ratio

Two conductors are made of the same material and have the same length. Conductor $A$ is a solid wire of diameter $1.0 \, mm$. Conductor $B$ is a hollow tube of outside diameter $2.0 \, mm$ and inside diameter $1.0 \, mm$. The resistance ratio $R_A/R_B$ will be

For which material does resistivity decrease with an increase in temperature?