Constantan wire is used in making standard resistances because its

Resistivity of which of the following substances decreases on increasing the temperature?

Which of the following graphs represents the variation of resistivity ( $\rho$ ) with temperature $(T)$ for copper?

Dimensions of a block are $1 \, cm \times 1 \, cm \times 100 \, cm$. If the specific resistance of its material is $3 \times 10^{-7} \, \Omega \cdot m$,the resistance between the square faces is:

At what temperature will the resistance of a copper wire become three times its value at $0^{\circ}C$? (Temperature coefficient of resistance for copper = $4 \times 10^{-3} \,^{\circ}C^{-1}$)

The length and area of cross-section of a copper wire are respectively $30 \ m$ and $6 \times 10^{-7} \ m^2$. If the resistivity of copper is $1.7 \times 10^{-8} \ \Omega \ m$,then the resistance of the wire is (in $\Omega$)