Question

calculate the resistance of a metal wire of length 2 metre and area of cross section 1.55* 10^-6 m^2, if the resistivity of the metal be 2.8*10^-8 ohm mtr.

Answer 1

We know that
R = (pl)/A
where R = resistance of the conductor (wire in this case)
p = resistivity of the wire
l = length of wire
A = area of cross section of wire
Putting corresponding values we get
R = { (2.8*10^-8)*(2) } / 1.55*10^-6
R ~3.6*10^-2