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The drift velocity of the electrons in a...

The drift velocity of the electrons in a copper wire of length 2 m under the application of a potential difference of 220V is `0.5ms^-1` . Their mobility ( in `m^2v^-1s^-1`)

A

`2.5 xx 10^(-3)`

B

`2.5 xx 10^(-2)`

C

`5 xx 10^(2)`

D

`5 xx 10^(-3)`

Text Solution

Verified by Experts

The correct Answer is:
D
`v_(d) = 0.5 m//s, E = V/l = 200/2 = 100 V//m`
Mobility `= mu = v_(d)/E = 0.5/100 = 5 xx 10^(-3) m^(2)//Vs`
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