If the 0.300-mA current through the calculator mentioned in the Example 20.1 example is carried by electrons, how many electrons per second pass through it?

Strategy

The current calculated in the previous example was defined for the flow of positive charge. For electrons, the magnitude is the same, but the sign is opposite, I_electrons = -0.300 × 10^-3 C/s. Since each electron (e^-) has a charge of -1.60 × 10^-19 C, we can convert the current in coulombs per second to electrons per second.