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The electron drift speed in metals is sm...

The electron drift speed in metals is small `(~ ms^(-1))` and the charge of the electron is also very small `(~ 10^(-19)C)`, but we can still obtain a large amount of current in a metal. Why?

Text Solution

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Current through a metal, `I = n A eV_(d)`.
A is the area of corss-section of the metal. The electron drift speed, `V_(d) (~ 10^(-5) ms^(-1))` is small. The charge of electron, `e (~ 1.6 xx 10^(-19) C)` is also very small. But we can still obtain a large amount of current in a metal due to presence of large number of free electrons (n) is a conductor `(~ 10^(29) m^(-3))`.
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