Question

calculator resistivity of metallic wire of length 1 metre and diameter 0.5 mm and resistance is 10 ohm
plzz answer this it's urgent please help​ frnds plss help me please I will mark brainlist

Answer 1

Given:

A metallic wire of length 1 metre and diameter 0.5 mm and resistance is 10 ohm.

To Find:

Calculate the resistivity of metallic wire.

Solution:

$\mathbf{Length \ of \ metallic \ wire\ = L = 1 \ m}$

$\mathbf{Resistance \ of\ metallic\ \ wire\ = R = 10 \ \ \ \Omega }$

$\mathbf{Diameter \ of\ metallic\ \ wire\ = d = 0.5 \ \ \ mm= 0.0005 \ m }$

$\mathbf{Cross-sectional\ area \ of \ wire\ = A = \frac{22}{7}\times \frac{0.0005^{2}}{4} \ \ \ m^{2} }$

We know the relation between resistance and resistivity of wire:

$\mathbf{R=\rho \dfrac{L}{A}}$

So resistivity can be written as:

$\mathbf{\rho =\dfrac{RA}{L}}$

On putting respective value in above equation:

$\mathbf{\rho =\dfrac{10\times 22\times 0.0005^{2}}{1\times 7\times 4}}$

$\mathbf{\rho =1.96\times 10^{-6} \ \ \ \Omega -m}$

Means resistivity of metallic wire is $\mathbf{1.96\times 10^{-6} \ \ \ \Omega -m}$.