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A metal wire of current density is 3.2 x...

A metal wire of current density is `3.2 xx10^(7)Am^(-2)` has `10^(28)` electrons `//m^(3)`. The average drift velocity is _______

A

`0.02 ms^(-1)`

B

`200ms^(-1)`

C

`1.6xx10^(-2) ms^(-1)`

D

`3xx10 ms^(-1)`

Text Solution

Verified by Experts

The correct Answer is:
A
`J= env_(d)`
`v_(d)=(J)/("ne")=(3.2xx10^(7))/(10^(28)xx1.6xx10^(-19))=0.02m s^(-1)`
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