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प्रश्न
Obtain the expression for the current flowing through a conductor having number density of the electron n, area of cross-section A in terms of the drift velocity vd .
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उत्तर
`1/N sum_(i = 1)^N V_i = 0`
`a = (-eM)/m`
`V_i = v_i - (eE)/m t_1`
`= 0 -(eM)/m τ = - (eE)/m τ`
`I Delta t = + n e A |V_d | Delta t`
`|j| = ( "ne" ^2)/m τ |E|`
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