1. The problem statement, all variables and given/known data Estimate the net force between the CO group and the HN group shown in the figure. The C and O have charges ±0.40e and the H and N have charges ±0.20e where e = 1.6 × 10-19 C. [Hint: Do not include the "internal" forces between C and O, or between H and N.] http://www.webassign.net/gianpse4/21-70.gif 2. Relevant equations Felec=kQ1Q2/r^2 k=9*10^9 3. The attempt at a solution First I tried going between O- and H+ as in: F=(k(-.4*.2)(1.6*10^-19)^2)/(.18*10^-9)^2 which didn't work. I could try the charges on each by the opposite two poles, but if I'm doing that why not try include the internal forces while I'm at it? Basically, without including the internal forces I'm not sure where to start. Also, I have only one attempt left so I wanted to check on here to see if I can get a push in the right direction. Thank you in advance!