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Question
Estimate the average drift speed of conduction electrons in a copper wire of cross-sectional area 2·5 × 10−7 m2 carrying a current of 2·7 A. Assume the density of conduction electrons to be 9 × 1028 m−3
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Solution
We know that drift velocity,
`V_d=I/(nAq)`
where I is the current, n is charge density, q is charge of electron and A is cross-section area.
`V_d=2.7/(9xx10^28xx2.5xx10^(-7)xx1.6xx10^(-19)`
`V_d=7.5xx10^(-4) `
This is the required average drift velocity.
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