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Mobility of electrons in a semiconductor is defined as the ratio of their drift velocity to the applied electric field. If, for an n-type semiconductor, the density of electrons is 10 19 m –3 and their mobility is 1.6 m 2 /(V.s) then the resistivity of the semiconductor (since it is an n-type semiconductor contribution of holes is ignored) is close to :

1. 0.4 Ω m
2. 2 Ω m
3. 4 Ω m
4. 0.2 Ω m

Correct answer: 0.4 Ω m

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