How many electrons per second constitute a current of one micro ampere?
Correct answer: D. 6.25 x 10^12 electrons
- A. one electron
- B. 10 -6 electrons
- C. 106 electrons
- D. 6.25 x 10^12 electrons
Explanation
Current is charge transferred per second, so the number of electrons per second is I/e = 1 x 10^-6 coulomb per second ÷ 1.6 x 10^-19 coulomb = 6.25 x 10^12 electrons per second. Therefore, option d gives the correct rate. The likely choice is c, because the micro prefix is incorrectly treated as giving 10^6 electrons rather than dividing the current by the extremely small charge of one electron.
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