Question

As you walk across a synthetic-fiber rug on a cold, dry winter day, you pick up an excess charge of -56?C .

Part A

How many excess electrons did you pick up?

Express your answer using two significant figures.

N =

Part B

What is the charge on the rug as a result of your walking across it?

Express your answer to two significant figures and include the appropriate units.

Q =

Answer 1

An electron has a charge of: q = -1.6*10^-19 C.

-54 uC of charge:

[(1 electron)/(-1.6*10^-19 C)]*[-56*10^-6 C ]

= 33.75*10^13 excess of electrons.

The rug was neutral before you walked on it. Now that you picked up an excess of :

-56uC

The rug now has a positive charge of:

+56uC

Answer 2

A) Each electron has a charge of -1.6 x 10^-19 C.
So, N electrons would have a charge of -(N x 1.6 x 10^-19) C.

Again, the total charge is -56 $\mu$C = -56 x 10^-6 C

So, -(N x 1.6 x 10^-19) = -56 x 10^-6

or N = 35 x 10^13

B) The total charge is 0. Every electron on you came from the rug. So the rug has the eqaul but opposite charge from you. So Q = 56 $\mu$C