(a) the resistance $\mathrm{\Omega}$

(b) the resistivity $\mathrm{\Omega}\cdot m$

Aphroditeoq
2022-07-21
Answered

A potential difference of 14 V is found to produce a current of 0.45 A in a 3.8 m length of wire with a uniform radius of 0.36 cm. Find the following values for the wire:

(a) the resistance $\mathrm{\Omega}$

(b) the resistivity $\mathrm{\Omega}\cdot m$

(a) the resistance $\mathrm{\Omega}$

(b) the resistivity $\mathrm{\Omega}\cdot m$

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Shelby Strong

Answered 2022-07-22
Author has **9** answers

We know that Resistance

R=V/I

And resistivity p=RA/L

a) Resistance

$R=\frac{V}{I}=\frac{14}{0.45}\phantom{\rule{0ex}{0ex}}R=31.11\mathrm{\Omega}$

b)$\rho =\frac{RA}{L}\phantom{\rule{0ex}{0ex}}\rho =\frac{\pi x(0.36\times {10}^{-2}{)}^{2}\times 31.11}{3.8}\phantom{\rule{0ex}{0ex}}\rho =3.3\times {10}^{-4}\mathrm{\Omega}-m$

R=V/I

And resistivity p=RA/L

a) Resistance

$R=\frac{V}{I}=\frac{14}{0.45}\phantom{\rule{0ex}{0ex}}R=31.11\mathrm{\Omega}$

b)$\rho =\frac{RA}{L}\phantom{\rule{0ex}{0ex}}\rho =\frac{\pi x(0.36\times {10}^{-2}{)}^{2}\times 31.11}{3.8}\phantom{\rule{0ex}{0ex}}\rho =3.3\times {10}^{-4}\mathrm{\Omega}-m$

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