Question

In pure semiconductor, the number of conduction electrons is `6 xx 10^18` per cubic metre. How many holes are there in a sample of size 1 cm x 1 cm x 1 mm?
A. `3xx10^10`
B. `6xx10^11`
C. `3xx10^11`
D. `6xx10^10`

Answer 1

Correct Answer - B
Here, `n_e=6xx10^18 m^(-3)`
Volume of the sample = 1 cm x 1 cm x 1 mm =`10^(-7) m^3`
Number of holes in the sample = Number of electrons in the sample.
`=n_exxV=6xx10^18 xx 10^(-7)=6xx10^11`