1. The problem statement, all variables and given/known data Consider an electron-proton pair and compare its electrostatic force with that of the gravitational force [G=6.67x10^11 Nm^2/kg^2]. 2. Relevant equations F = k * |q1 * q2| / r^2 k = 1/4π∈ 3. The attempt at a solution I calculated the force by using the charge of an electron squared (abs value) with an arbitrary r^2. I don't understand what the question is asking? Compare it to what? My textbook's answer says Fe/Fg is the answer. That's nice. I'm more interested in the why this is important part and which gravitational force we're dealing with.