Calculate the resistivity of an n-type semiconductor from the following data:density of conduction electrons `=8xx10^13cm^(-3)`,density of holes `=5xx10^12cm^(-3),`mobility of conduction electron `=2.3xx10^(4)cm^(2)V_(-1)s_(-1)`and mobility of holes`=100cm^(2)V_(-1)s_(-1 ).`

Explanation

The conductivity of the semiconductor is
`(sigma)=e(n_(e)(mu_e)+n_(h)(mu)_h)`
`=(1.6xx10_(-19)C)[(8xx10^(19)m(-3))xx(2.3m^(2)V^(-1)s^(-1)+(5xx10^(18)m^(-3))xx(10^(-2)m^(-2)V^(-1)s^(-1)]`
`~~2.94Cm^(-1)V^(-1)s^(-1).`
`The resistivity is `(rho)=1/(sigma)=1/(2.94)mVsC^(-1)~~0.34(Omega)m.`