One end of an aluminium wire whose diameter is 2.5 mm is welded to one end of a copper wire whose diameter is 2.0 mm. The composite wire carries a steady current of 6.25A. What is the current density in each wire ?

Copper has one conduction electron per atom. Its density is 8.89g//cm^3 and Its atomic mass is 63.54.g//mol . If a copper wire of diameter 1.0 mm carries a current 2.0 A. The drift speed of the electrons in the wire is

A copper sphere of radius 3 cm is beaten and drawn into a wire of diameter 0.2 cm. The length of the wire is____

At a junction of three wires , the inward currents through two of the wire are 1 A and 2 A . What is the inward current though the third wire ?

The length of a wire is 10 m and the diameter is 2 mm . If the resistivity of substance of the wire is 2 xx 10^(-6) ohm . Then the resistance of the wire is

A cell of emf 2Vand internal resistance 1.5Omega is connected to two ends of 100 cm wire. The resistance of the wire is 0.005 Omega//cm. The potential gradient of the wire is

The radius of a copper wire is twice that of a steel wire. One end of the copper wire is joined with one end of the steel wire and the same tensile force is applied on them . If the length of the copper wire increases by 1% , what will be the percentage increase in the length of the steel wire? Given Young's modulus of steel is twice that of copper.

An 8kg mass is suspended from one end of an iron wire of length 2 m and diameter 1mm. IF the young's modulus of iron is 2 times 10^12 dyn. cm^-2 , then what is the increase in length of the wire? [ g=980 cm.s^-2 ]