Find the resistance of a cube of edge $60 \text{ cm}$,made of a material of specific resistance $60 \times 10^{-8} \Omega \text{ m}$.

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

$A$ wire of resistance $R$ is stretched until its radius is halved. What will be the new resistance (in $, R$)?

At what temperature $(^oC)$ will the resistance of a copper wire become three times its value at $0^oC$? (Given: Temperature coefficient of resistance of copper at $0^oC$ is $\alpha = 4 \times 10^{-3} / ^oC$)

$A$ thick wire is stretched so that its length becomes two times. Assuming that there is no change in its density,what is the ratio of the change in resistance of the wire to the initial resistance of the wire?

In order to quadruple the resistance of a uniform wire,a part of its length $x$ was uniformly stretched till the final length of the entire wire was $1.5$ times the original length $l$. The fraction of the wire that was stretched,$x/l$,is equal to: