In a conductor, if the number of conduction electrons per unit volume is 8.5 × 1028 m-3 and mean free time is 25 fs (femto second), it's approximate resistivity is: (me = 9.1 × 1031 kg)

Question

In a conductor, if the number of conduction electrons per unit volume is 8.5 × 1028 m-3 and mean free time is 25 fs (femto second), it's approximate resistivity is: (me = 9.1 × 1031 kg) (A) 10-5 Ω m (B) 10-6 Ω m (C) 10-7 Ω m (D) 10- 8 Ω m

Tardigrade Admin · Accepted Answer

ρ = (m/ne2 τ) = 1.67 × 10-8 Ω m

Q. In a conductor, if the number of conduction electrons per unit volume is $8.5 \times 1 0^{28} m^{- 3}$ and mean free time is $25 f s$ (femto second), it's approximate resistivity is :
$(m_{e} = 9.1 \times 1 0^{31} k g)$

$1 0^{- 5} Ω m$

$1 0^{- 6} Ω m$

$1 0^{- 7} Ω m$

$1 0^{- 8} Ω m$

$ρ = \frac{m}{n e ^{2} τ}$
$= 1.67 \times 1 0^{- 8} Ω m$

Q. In a conductor, if the number of conduction electrons per unit volume is 8.5×1028m−3 and mean free time is 25fs (femto second), it's approximate resistivity is : (me​=9.1×1031kg)

10−5Ωm

10−6Ωm

10−7Ωm

10−8Ωm