# Homework Help: Numericals On Electrostatics (including Coloumbs Law) ! !

1. Dec 2, 2009

### srijit92

1. In hydrogen atom the distance between electron(e=1.6*10^-19 C)(Mass of electron=9.1*10^-31 kg) & proton(Mass Of proton=1.7*10^23 C) is 5.3*10^-11 m.

2. Calculate the electrical and gravitational forces between 2 particles

2. Dec 2, 2009

### jdwood983

Welcome to PF!

What equations do you have for the gravitational force and the electric force?

3. Dec 2, 2009

### jdwood983

So you know that

$$F_{gravity}=G\frac{m_1m_2}{r^2}$$

so then you are given both masses, the distance apart and the gravitational constant, so this should be a straight-forward "enter the variables" type problem.

But what about the $F_{electric}$, what is the equation for that? (Hint: it has a similar form as the gravitational force)