 Once you've gone over your pre-lecture material, you should be ready to start on the practice problem for today's virtual lecture. This is the worksheet that was handed out in class on Friday, or you can print the PDF form off of blackboard. We're going to start on the front side with this first problem here, and we're looking at two charges which are located on the x-axis. I'll let you read the whole problem in detail. On part A, we're supposed to draw a quick diagram of the two charges. Indicating their positions and the direction of force on each particle. Now I've already got part of the diagram drawn here, just because on the computer it takes a little bit more steps to actually get everything drawn. But I've got a line representing my x-axis. And then I've placed my two particles along that line. Now I could have drawn in little tick marks to show you where you've got 0.1, 0.2, 0.3 Well, I don't have it spaced out, right? 0.4 and then 0.5 would be over here to show where everything is. And I've got my two charges labeled as Q1 and Q2. Now to figure out the forces on each particle, you want to notice that Q1 is positive while Q2 is negative. And that means these two are going to attract. So when I draw in my forces, I want to have the force on charge 1 pointing towards charge 2 and the force on charge 2 pointing towards charge 1. That way the two particles are showing that they're being attracted to each other. So you can have a very simple diagram like this, or you can draw in your little tick mark showing you a little bit better how far the charges are apart on that x-axis.