If resistivity of copper is 1.72 × 10-8 Ω-m and number of free electrons in copper is 8.5 × 1028 / m 3. Find mobility.

Question

If resistivity of copper is 1.72 × 10-8 Ω-m and number of free electrons in copper is 8.5 × 1028 / m 3. Find mobility. (A) 4.25 × 10-3 m 2 / C Ω (B) 6.8 × 10-3 m 2 / C Ω (C) 8.5 × 10-3 m 2 / C Ω (D) 3.4 × 10-3 m 2 / C Ω

Tardigrade Admin · Accepted Answer

Given, Resistivity of Copper = 1.72 × 10-8 Ω-m Number of free electrons, n = 8.5 × 1028 /m3 Mobility, μ = (1/ρ ne) =(1/1.72×10-8Ω m×8.5×1028/m3×1.6×10-19) =4.25×10-3m2/CΩ

Q. If resistivity of copper is $1.72 \times 1 0^{- 8} Ω$ -m and number of free electrons in copper is $8.5 \times 1 0^{28} / m^{3}$ . Find mobility.

$4.25 \times 1 0^{- 3} m^{2} / C Ω$

$6.8 \times 1 0^{- 3} m^{2} / C Ω$

$8.5 \times 1 0^{- 3} m^{2} / C Ω$

$3.4 \times 1 0^{- 3} m^{2} / C Ω$

Given,
Resistivity of Copper = 1.72 $\times$ 10^-8 $Ω$ -m
Number of free electrons, n = 8.5 $\times$ 10²⁸ /m3
Mobility, $μ = \frac{1}{ρ n e}$
$= \frac{1}{1.72 \times 1 0 ^{- 8} Ω m \times 8.5 \times 1 0 ^{28} / m ^{3} \times 1.6 \times 1 0 ^{- 19}}$
$= 4.25 \times 1 0^{- 3} m^{2} / C Ω$

Q. If resistivity of copper is 1.72×10−8Ω-m and number of free electrons in copper is 8.5×1028/m3. Find mobility.

4.25×10−3m2/CΩ

6.8×10−3m2/CΩ

8.5×10−3m2/CΩ

3.4×10−3m2/CΩ