In pure semiconductor, the number of conduction electrons is 6 × 1018 per cubic metre. How many holes are there in a sample of size 1 cm × 1 cm × 1 mm?

Question

In pure semiconductor, the number of conduction electrons is 6 × 1018 per cubic metre. How many holes are there in a sample of size 1 cm × 1 cm × 1 mm? (A) 3 × 1010 (B) 6 × 1011 (C) 3 × 1011 (D) 6 × 1010

Tardigrade Admin · Accepted Answer

Here, ne = 6 × 1018 m-3 Volume of the sample = 1 cm × 1 cm × 1 mm = 10-7 m3 Number of holes in the sample = Number of electrons in the sample = ne × V = 6 × 1018 × 10-7 = 6 × 1011

Q. In pure semiconductor, the number of conduction electrons is $6 \times 1 0^{18}$ per cubic metre. How many holes are there in a sample of size $1 c m \times 1 c m \times 1 mm$ ?

$3 \times 1 0^{10}$

$6 \times 1 0^{11}$

$3 \times 1 0^{11}$

$6 \times 1 0^{10}$

Here, $n_{e} = 6 \times 1 0^{18} m^{- 3}$
Volume of the sample $= 1 c m \times 1 c m \times 1 mm$
$= 1 0^{- 7} m^{3}$
Number of holes in the sample = Number of electrons in the sample
$= n_{e} \times V$
$= 6 \times 1 0^{18} \times 1 0^{- 7}$
$= 6 \times 1 0^{11}$

Q. In pure semiconductor, the number of conduction electrons is 6×1018 per cubic metre. How many holes are there in a sample of size 1cm×1cm×1mm?

3×1010

6×1011

3×1011

6×1010