The right hand rule you used in problem 1 implies that charges ow- ing in a wire would similarly feel a force. So, suppose the eld is up, and the current in the wire is to the right, as shown in Figure 3. A. What would be the direction of the force on the wire? B. If the current is to the right, we could think of positive charges moving to the right, but we know that in metal wires like these, negative charges are really moving to the left. Does that make a difference in the direction of the force on the wire? C. If the wire were oriented parallel to the magnetic eld, what does the rule say the force would be? Currents also cause magnetic elds! Again, there's a right-hand- rule: Point your right thumb in the direction of the current along a wire and curl your ngers around the wire. The magnetic eld vectors due to a current in the direction of your thumb goes in circles around the wire. D. Using this rule and the rule we used in question 3, will two wires carrying current in the same direction be pulled toward each other or repelled apart? 1% 1% 1H E. Does your answer to part D agree with the idea that likes repel? F. Use this same rule to sketch the magnetic eld caused by cur- rent owing in a loop of wire shown in Figure 5. B Figure 3: Current moving through a magnetic eld. Note that this is the magnetic field caused by this current, whereas previous questions were asking about the force on a wire in a magnetic eld caused by other sources. second wire with current Figure 4: A second wire shown in blue (and with current run- ning through it) is placed next to the first one (for which mag- netic field is depicted). current Figure 5: Current flowing in a loop of wire in the directions shown