with columns. Law, We have our columns law formula where e. Which is our potential energy or force in Newtons. In physics, you would see this variable as 1/4 pi. Same vary variable with sub not but for simplicity. I'm just having it. Is that single variable here? We're going to say that it is in place off what we call the permitted constant, which is 9.0 times 10 to the nine Newtons. Times meter squared over Coolum squared Q one and Q two represent our particles one and two that are in columns or absolute charge. Our, which down here would actually be r squared equals the distance off the ion centers in meters. Not finally, just remember that the absolute charge of an ion is equal to 1.602 times 10 to the negative 19 cool apps. That would mean that if you had a charge of, let's say, plus two, that's your absolute charge. But how would you convert it to cool them? You will just multiply by that same value, and that would be 3.204 times 10 to the negative Coolio's so now that we know comes law formula. Let's move on to the next video and take a look at the example question.