# Its really urgent!!! Derivation of I=neAVd. ?

let no. of electrons per unit volume=n
charge on an atom=e

no.of electrons in length l of the conductor=n×volume of conductor=nAl

total charge contained in the conductor is
q=neAl

all the electrons which enter the conductor at the right end will pass through the left end of the conductor in time,
t=distance/velocity
=l/vd

therefore,current,
I=q/t=enAl/(l/vd)
=> I=neAvd
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hope it helps better cheers !!!
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Derivation of I=neAVd

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Consider a conductor with cross sectional are A.
Assume that the ends of the conductor are connected to a battery to make the current flow through it.

Let Vd be the drift speed of charge.
Let n be the number of charges present in the conductor in an unit volume.
The distance covered by each charge in one second is Vd.
Then the volume of the conductor for this distance is equal to AVd.

The number of charges contained in that volume is equal to nAVd.
Let q be the charge of each carrier.
Then the total charge crossing the cross sectional area at poisition D in one second is nqAVd.
Hence
electric current I=nqAVd.

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