A negatively charged balloon has 3.1 μC of
charge.
How many excess electrons are on this bal-
loon?
Answer in units of electrons.
To find the number of excess electrons on the balloon, we need to use the fundamental charge of an electron and the charge on the balloon.
The fundamental charge of an electron is approximately -1.6 x 10^-19 coulombs.
We are given that the balloon has a charge of -3.1 μC. To convert this to coulombs, we need to multiply by 10^-6 since μ (micro) means 10^-6.
Therefore, the charge on the balloon in coulombs is -3.1 μC * 10^-6 = -3.1 x 10^-6 C.
Now, we can find the number of excess electrons by dividing the charge on the balloon by the charge of a single electron.
Number of excess electrons = Charge on balloon / Charge of an electron
Number of excess electrons = (-3.1 x 10^-6 C) / (-1.6 x 10^-19 C)
Dividing these two values, we get:
Number of excess electrons ≈ 1.94 x 10^13 electrons
Hence, there are approximately 1.94 x 10^13 excess electrons on the balloon.