Mobilities of electrons and holes in a sample of intrinsic germanium at room temperature are 0.54 m2 V-1 s-1 and 0.18 m2 V-1 s-1 respectively. If the electron and hole densities are equal to 3.6 × 1019 m-3 the germanium conductivity is

Question

Mobilities of electrons and holes in a sample of intrinsic germanium at room temperature are 0.54 m2 V-1 s-1 and 0.18 m2 V-1 s-1 respectively. If the electron and hole densities are equal to 3.6 × 1019 m-3 the germanium conductivity is (A) 4.14 S m-1 (B) 2.12 S m- 1 (C) 1.13 S m-1 (D) 5.6 S m-1

Tardigrade Admin · Accepted Answer

Given in question,
Mobilities of electrons

μ_{e} = 0.36 \times m^{2} V^{- 1} s^{- 1}

Mobilities o holes

μ_{h} = 0.17 \times m^{2} V^{- 1} s^{- 1}

densities of electron

=

densities of holes

= 2.5 \times 1 0^{19} m^{- 3}

As we know, conductivity,

σ = \frac{1}{p} = e (μ_{e} n_{e} + μ_{n} n_{n})

= 1.6 \times 1 0^{- 19} [0.36 \times 2.5 \times 1 0^{19} + 0.17 \times 2.5 \times 1 0^{19})]

= 2.12 S m^{- 1}

So the electrical conductivies of germanium is

2.12 S m^{- 1}

Q. Mobilities of electrons and holes in a sample of intrinsic germanium at room temperature are $0.54 m^{2} V^{- 1} s^{- 1}$ and $0.18 m^{2} V^{- 1} s^{- 1}$ respectively. If the electron and hole densities are equal to $3.6 \times 1 0^{19} m^{- 3}$ the germanium conductivity is

$4.14 S m^{- 1}$

$2.12 S m^{- 1}$

$1.13 S m^{- 1}$

$5.6 S m^{- 1}$

Q. Mobilities of electrons and holes in a sample of intrinsic germanium at room temperature are 0.54m2V−1s−1 and 0.18m2V−1s−1 respectively. If the electron and hole densities are equal to 3.6×1019m−3 the germanium conductivity is

4.14Sm−1

2.12Sm−1

1.13Sm−1

5.6Sm−1

Q. Mobilities of electrons and holes in a sample of intrinsic germanium at room temperature are $0.54 m^{2} V^{- 1} s^{- 1}$ and $0.18 m^{2} V^{- 1} s^{- 1}$ respectively. If the electron and hole densities are equal to $3.6 \times 1 0^{19} m^{- 3}$ the germanium conductivity is

$4.14 S m^{- 1}$

$2.12 S m^{- 1}$

$1.13 S m^{- 1}$

$5.6 S m^{- 1}$