Calculate the drift velocity of free electrons if a current of 5 A is maintained in a conductor of cross-section 10^-2m^2. The number density of free electrons is 5 × 10^20m^-3.(a) 6.25 ms^-1(b) 5.25 ms^-1(c) 2.25 ms^-1(d) 12.25 ms^-1I had been asked this question during an online interview.This interesting question is from Current Electricity topic in division Current Electricity of Physics – Class 12

Calculate the drift velocity of free electrons if a current of 5 A is

1.	Calculate the drift velocity of free electrons if a current of 5 A is maintained in a conductor of cross-section 10^-2m^2. The number density of free electrons is 5 × 10^20m^-3.(a) 6.25 ms^-1(b) 5.25 ms^-1(c) 2.25 ms^-1(d) 12.25 ms^-1I had been asked this question during an online interview.This interesting question is from Current Electricity topic in division Current Electricity of Physics – Class 12
Answer» Right option is (a) 6.25 ms^-1 The BEST explanation: Drift velocity = \(\FRAC {CURRENT}{(number \, density \, of \, electrons \, \times \, charge \, on \, electron \, \times \, Area)}\). \(\frac {5}{(5 \times 10^{20} \times 1.6 \times 10^{-19} \times 10^{-2})}\) = 6.25 ms^-1.

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