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3 years ago

Estimate the current density in copper wire at 20 °C if an electric field of 0.923 V/m exists within

Physics

1 answer:

hoa [83]3 years ago

4 0

We have that the estimated the current density in copper wire at 20 °C is

$J=38*10^6A/m^2$

From the question we are told

the current density in copper wire at 20 °C
if an electric field of 0.923 V/m exists within the wire

Generally the equation for the current density is mathematically given as

current density

$J=\alpha E$

Where

$\alpha=\frac{1}{e}\\\\\\alpha=\frac{1}{2.44*10^{-8}}\\\\\alpha=4.09*10^7$

Therefore

$J=4.09*10^7* 0.923$

$J=38*10^6A/m^2$

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