Magnetism Problem?

Question

A packed bundle of 100 long, straight, insulated wires forms a cylinder of radius R=.5cm

a. if each wire carries 2A, what are the magnitude and direction of the magnetic force per unit length acting on a wire located .2cm from the center of the bundle?

don't know what to do.

Answer 1

The question is poorly worded and ambiguous. Is the test wire parallel to the axis? Are the wires equally spaced? Can we assume they are very thin compared to the radius? Can we use a uniform surface current approximation, or are we looking for the perturabitve effects due to deviations from uniformity? Does the test wire have current? What current?

Unless you're suppose to divine that you can use a uniform surface current approximation to get zero force, you're suppose to use superposition of multiple two parallel wire forces. But, if you were actually asked such an ill posed question, you have a really bad teacher. Did you just write it down incorrectly? You poor confused lil angel.