The resistance of a wire is \(R\) ohm. If it is melted and stretched to \(n\) times its original length, its new resistance will be:
1. \(nR\)
2. \(\frac{R}{n}\)
3. \(n^2R\)
4. \(\frac{R}{n^2}\)

Two solid conductors are made up of the same material and have the same length and the same resistance. One of them has a circular cross-section of area $A_1$ and the other one has a square cross-section of area $A_2$. The ratio $A_1/A_2$ is:

A wire of resistance \(4~\Omega\) is stretched to twice its original length. The resistance of a stretched wire would be:
1. \(4~\Omega\)
2. \(8~\Omega\)
3. \(16~\Omega\)
4. \(2~\Omega\)

The specific resistance of a conductor increases with:

The dependence of resistivity \((\rho)\) on the temperature \((T)\) of a semiconductor is, roughly, represented by:

1.		2.
3.		4.

Two metal wires of identical dimensions are connected in series. If ${\mathrm{}}_{}$\(\sigma_1\) $\mathrm{and}$ \(\sigma_2\) are the conductivities of the metal wires respectively, the effective conductivity of the combination is:

Variation of current passing through a conductor with the voltage applied across its ends varies is shown in the diagram below. If the resistance (R) is determined at points A, B, C and D, we will find that: