A 14-gauge copper wire of diameter 1.628 mm carries a current of 12.5 What is the potential difference across a 2.00 - m length of the wire? *p=1.47x10^-8

Respuesta :

Answer:

[tex]V=1.76\times 10^{-4}\ V[/tex]

Explanation:

Given that,

The diameter of a wire, d = 1.628 mm

Radius, r = 0.814  mm = 0.000814m

Current, I = 12.5 mA

The length of the wire, l = 2m

The resistivity of the wire, [tex]\rho=1.47\times 10^{-8}\ \Omega-m[/tex]

We need to find the potential difference across the wire. We know that the resistance of the wire is given by :

[tex]R=\rho\dfrac{l}{A}[/tex]

Also, V = IR

[tex]\dfrac{V}{I}=\rho\dfrac{l}{A}\\\\V=\dfrac{\rho l I}{A}\\\\V=\dfrac{1.47\times 10^{-8}\times 2\times 12.5\times 10^{-3}}{\pi \times (0.000814)^2}\\\\V=1.76\times 10^{-4}\ V[/tex]

So, the potential difference of the wire is [tex]1.76\times 10^{-4}\ V[/tex].