A potential difference of 100 V is applied across a conductor of length 50cm. Calculate the drift velocity of electrons if the electron mobility is 9 × 10^-5 m^2V^-1s^-1.(a) 0.001 ms^-1(b) 1.800 ms^-1(c) 0.018 ms^-1(d) 0.180 ms^-1The question was posed to me during an interview.Question is from Current Electricity in section Current Electricity of Physics – Class 12

A potential difference of 100 V is applied across a conductor of lengt

1.	A potential difference of 100 V is applied across a conductor of length 50cm. Calculate the drift velocity of electrons if the electron mobility is 9 × 10^-5 m^2V^-1s^-1.(a) 0.001 ms^-1(b) 1.800 ms^-1(c) 0.018 ms^-1(d) 0.180 ms^-1The question was posed to me during an interview.Question is from Current Electricity in section Current Electricity of Physics – Class 12
Answer» Correct answer is (c) 0.018 ms^-1 Easiest explanation: Drift velocity = Mobility × ELECTRIC field. It can be REARRANGED as, Drift velocity = \(\frac {(mobility \, \TIMES \, Potential \, DIFFERENCE)}{LENGTH}\). Drift velocity = \(\frac {(9 × 10^{-5} \times 100)}{0.5}\) = 0.018 ms^-1.

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