# Homework Help: Charged particle interaction

1. Apr 6, 2010

### Sashikala

1. The problem statement, all variables and given/known data
What is the force of attraction between a uranium nucleus(atomic number 92)
and an electron at a distance of 0.1 nm?

2. Relevant equations

F = kQ1Q2/r2

3. The attempt at a solution

F= 8.99*109*92*1.6*10-19*(-1.6*10-19)/0.1*10-9

Please let me know the attempt at a solution is correct.

2. Apr 6, 2010

### Cilabitaon

well, using Coulomb's Force(like you did), you get the equation

$$F=\frac{1}{4 \pi \epsilon_{0}} \cdot \frac{Q_{U}Q_{e^{-}}}{r^{2}}$$

Which then, by substitution:

$$F=\frac{1}{4 \pi \times 8.85 \times 10^{-12}} \cdot \frac{(92 \times 1.6 \times 10^{-19}) \cdot (-1.6 \times 10^{-19})}{(0.1 \times 10^{-9})^{2}}$$

3. Apr 6, 2010

### Kabbotta

Yeah, it looks like you just forgot to square the radial distance.