# GATE Papers >> ECE >> 2015 >> Question No 20

Question No. 20

A silicon sample is uniformly doped with donor type impurities with a concentration of 1016/cm3. The electron and hole mobilities in the sample are 1200 cm2/V-s and 400 cm2/V-s respectively. Assume complete ionization of impurities. The charge of an electron is 1.6 X 10-19 C. The resistivity of the sample (in $\mathrm{\Omega }$-cm) is _______.