I just saw an instructor of EEE (YouTube) talk about Cross Product. He gave an example of when cross products are used. Here's what he said. He drew a vertical arrow and said this is current. Then he drew a circular arrow around the vertical line and said it is B. Then he drew a smaller vector, maybe unit, I'm not sure, on the vertical one and drew a vector from the base of the second vertical one to a point on the B arrow, stating that the cross product has something to do with these two vectors. My question is since the current vector was not given a magnitude and neither was the B circle around the current arrow, how could one ever calculate the cross product. AND since B technically goes on to infinity, at what diameter do you consider the end of the B vector to stop? If it's infinite, then I'd say the vector is infinite.