Question

Resistivities of copper ,silver and magnin are $1.7\times {10}^{-8}\Omega m,1.0\times {10}^{-8}\Omega m$ and $44\times {10}^{-8}\Omega m$ respectively which of these is the best conductor ?

Answer 1

The expression for resistance of a conductor is:

$R=\rho \frac{l}{A}$

where, $\rho$ is the resistivity of the conductor.

So, resistance is directly proportional to the resistivity. Lesser the resistance offered by the conductor, better conductor it is.

Thus, out of copper, silver and magnin, the one with least resistivity and hence least resistance is silver. Thus, silver is the best conductor.