1. The problem statement, all variables and given/known data A rectangular loop of wire of size 5 cm x 15 cm is placed near a long straight wire with side CD at a distance of 5 cm from it, as shown in figure 6.29. What is the net force exetred on the loop (magnitude and direction)? How does your answer change if the current in the loop is reversed? 2. Relevant equations F = BIl B = 4pi-7/2pi x I/r 3. The attempt at a solution First I tried to figure out the net electric field at DC (same as AB). I added the magnetic field from the wire and the field from AB to get the net magnetic field at DC. But then I got confused, because what I have now is the net electric field. What lenght from the equation F=BIl should be used, is that 15 cm as that is the length of the loop? Or should I figure out the magnetic field from the wire and AB indivdually, calculate the force of each and then add them?