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Calculate the drift speed of the electro...

Calculate the drift speed of the electrons when 1A of current exists in a copper wire of cross section 2 `mm^(2)`.The number of free electrons in `1cm^(3)`of copper is `8.5xx10^(22)`.

Text Solution

Verified by Experts

we have
`j=nev_(d)`
or, `v_(d)=j/n e=i/A ne`
`(1A)/((2xx10^(-6)m^(2))(8.5xx10^(22)xx10^(6)m^(-3))(1.6xx10^(-19)C))`
`=0.036mm s^(-1)`.
We see that the drift speed is indeed small.
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