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In a semiconductor it is observed that three-quarters of the current is carried by electrons and one quarters by holes. If the drift speed is three times that of the holes, what is the ratio of electrons to holes?

In a semiconductor it is observed that three-quarters of the current is carried by electrons and one quarters by holes. If the drift speed is three times that of the holes, what is the ratio of electrons to holes? Correct Answer 1 : 1

In a semiconductor, I = Ie + Ih Here, Ie = 3⁄4 I and Ih = 1⁄4 I Now ve = 3vh Ie/Ih = nve/nvh 3 = 3n/p n = p Hence the ration is, 1 : 1

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