Two wires of equal lengths, one of copper and the other of manganin have equal resistance values. Which wire is thicker ? Explain.

Two wires of equal length, one of copper and the other of aluminium have the same resistance. Which of the two wires is lighter? Hence explain why aluminium wires are prefered for overhead power cables. (P_(Al) = 2.63 xx 10^(-8) Omega m , P_(Cu) = 1.72 xx 10^(-8) Omega m , Relative density of Al = 2.7 , of Cu = 8.9.

Copper is one of the suitable material to make connecting wires due to its low resistivity. A copper wire is in the form of a cylinder and has a resistance R. It is stretched till its thickness reduces by half of its initial size. Find its new resistance in terms of R.

Two heater wires of equal length are first connected in series and then in parallel. The ratio of heat produced in two cases is

Three copper wires have their lengths in the ratio 5:3:1 and their masses are in the ratio 1:3:5 . Their electrical resistance will be in the ratio.

A wire of resistance R ohm is stretched to double its length. What is the new resistance.