 Now, we can take a look at this next section on the worksheet for a very long straight wire. And all three of these questions have to do with the direction of the magnetic field. So I first want to remind you, if you take a look at the videos, that we're using the right hand thumb rule. So you want to make sure you're using your right hand, not your left hand when you're looking at that thumb. In this rule, it says that if you point your thumb in the direction of the current, then your fingers will curl around that wire in the direction of the magnetic field. For this particular example, our current is actually headed straight up the page, so it's going to look something like that. So if I sort of superimpose these two diagrams, what we can see is that the magnetic field is going to curve around this wire. Now it's kind of hard to see in 3D right from here. So instead of using our fingers, I've got a little arrow here. So the idea is just like these fingers curl, it comes around from behind the back, curls out, across in the front, and then back down in before going behind the wire again. So this is a side view of the system. And when you think about these questions over here, on the right side, on the left side, or directly in front of the wire, well, first of all, you can eliminate the up and down. That's the direction the current is going. The magnetic field is going around the wire. So over here on the right side, it's going in, behind, and as it moves behind it moves to the left. Then it comes out over here on the left side. And then as it moves across in front of it, it's moving towards the right in front of it. So that should give you a little bit of an idea. Now remember, if the current had been going in the opposite direction, then you'd want to actually take this and rotate it around. And it would show you that your fingers are going in the opposite direction around the circle. So you always have to make sure your thumb lines up with the direction of the current. Since this one went up, we want to go ahead and rotate that so that the thumb is in the upward direction.