Question

What is the electrical force of attraction between two balloons with separate charges of +3.5 x 10-8 C and -2.9 x 10-8 C when separated a distance of 0.65 m?

Answer 1

The answer is: `F=-2,16xx10^-5N`.

The law is:

`F=1/(4piepsilon_0)(q_1q_2)/r^2`, or `F=k_e(q_1q_2)/r^2`, where

`k_e=8,98*10^9C^-2m^2N` is the constant of Coulomb.

So:

`F=8,98xx10^9C^-2m^2N*(3,5xx10^-8C*(-2,9)xx10^-8C)/(0,65m)^2=`

`=-216xx10^-7N=-2,16xx10^-5N`.

A very detailed explanation of Coulomb's law is here: http://socratic.org/questions/what-is-the-electrical-force-of-attraction-between-two-balloons-with-separate-ch