A copper wire of diameter 1.0 mm carries a current of 0.2 A. Copper has `8.4xx10^(28)` atoms per cubic metre. Find the drift velocity of electrons, assuming that one charge carrier of `1.6xx10^(-19)` C is associated with each atom of the copper.

Answer

`5.6 xx 10^(-6)ms^(-1)`

Explanation

Here `D = 2.0mm = 2 xx 10^(-3) m, I= 2.4A`
`n = 8.5xx 10^(28)m^(-3), e = 1.6 xx 10^(-19)C`
`upsilon_(d) = (I)/(nAe) = (I xx 4)/(n pi D^(2)e)`
`= (2.4 xx 4)/((0.5 xx 10^(28))xx 3.14 xx(2 xx 10^(-3))xx(1.6 xx 10^(-19))`
`= 5.6 xx 10^(-6)ms^(-1)`