In a conductor, if the number of conduction electrons per unit volume is $8.5 \times 10^{28} m^{- 3}$ and mean free time is $25 f s$ (femto second), it’s approximate resistivity is: $(m_{e} = 9.1 \times 10^{- 31} k g)$

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In a conductor, if the number of conduction electrons per unit volume is 8.5 × 10 28 m - 3 and mean free time is 25 f s (femto second), it’s approximate resistivity is: m e = 9.1 × 10 - 31 k g

TestHub · Accepted Answer

We know i = n e Av d ⇒ i = V R = V A ρ l = E A ρ ρ = E A i = E A n e Av d Drift velocity can be written as v d = e E m e τ ρ = E A m e n e A e E τ = m e n e 2 τ = 9.1 × 1 0 - 31 8.5 × 1 0 28 × 1.6 × 10 - 19 2 × 25 × 1 0 - 15 ≈ 1.65 × 1 0 - 8 Ω m

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