Question

There are two strings made up of iron and silver of same thickness. Length of iron string is 6cm . Find the length of silver wire whose resistance equal to resistance of the iron wire. (Resistivity of the iron is 10*10-8 and resistivity of silver is 1.6*10-8)

Answer 1

The length of the silver wire is 37.5 cm

Explanation:

Given that,

Length of iron string, $l_i=6\ cm=0.06\ m$

Resistivity of iron, $\rho_i=10^{-7}\ \Omega-m$

Resistivity of silver, $\rho_s=1.6\times 10^{-8}\ \Omega-m$

The two strings are made up of iron and silver of same thickness. There areas will be same. The resistance of both silver and iron are same. The resistivity of any wire is given by :

$R=\rho\dfrac{l}{A}$

$\rho_i\times l_i=\rho_s\times l_s$

$l_s$ is the length of silver wire

$l_s=\dfrac{\rho_i\times l_i}{\rho_s}$

$l_s=\dfrac{10^{-7}\times 0.06}{1.6\times 10^{-8}}$

$l_s=0.375\ m$

$l_s=37.5\ cm$

So, the length of the silver wire is 37.5 cm. Hence, this is the required solution.

Learn more :

Topic : Resistivity and resistance

https://brainly.in/question/12965163

Answer 2

Explanation:

Given = Area of iron = Area of silver

Resistance of iron = Resistance of silver