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*10^(-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=(q)/(e)=(-14.41*10^(-6)C)/(-1.602*10^(-19)C)=8.995...*10^(13)`

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