Pure Si is experimentally determined to exhibit a carrier

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Pure Si is experimentally determined to exhibit a carrier (electron or hole) density of 1·48 × 10¹⁰ electrons (holes) cm³ at 300° K. If the electron mobility and hole mobility is 1300 cm²/Vs and 500 cm²/Vs, the resistivity of an intrinsic Si specimen at 300 °K is …………?

1. 2·3⁵ × 10⁵ Ω m
2. 1·18 × 10⁵ Ω m
3. 2·35 × 10⁵ Ωcm
4. Cannot be determined

Correct Option: C

Given
µ_i = 1·48 × 10¹⁰ cm³
µ_n = 1300 cm²/V–s
µ_p = 500 cm²/V–s
i =?

We know that, i =	1	=	1
	i		q n_i (µ_n + µ_p)

or i =	1
	1·6 × 10^–19 × 1·48 × 10¹⁰ (1300 + 500)

or i = 2·35 × 10⁵ Ω–cm
Hence alternative (C) is the correct choice.