Question

When you walk across a carpet during the winter you often get a shock when you touch a metal door knob. The reason is that you pick up electrons via friction between your feet and the carpet. If you pick up -14.41 microC of charge, how many electrons did you acquire ?

Answer 1

The charge e of a single electron is:

$e=-1.602\times10^{-19}C$

If you acquired a total of N electrons, picking up a charge q, then:

$Ne=q$

The charge picked up after a walk is given, and the charge of an electron is known. Isolate N from the equation and substitute the values for e and q=-14.41*10^(-6)C:

$N=\frac{q}{e}=\frac{-14.41\times10^{-6}C}{-1.602\times10^{-19}C}=8.995...\times10^{13}$

Therefore, you acquire approximately 8.995*10^(13) electrons.