Consider three circular turns flat, facing each other (parallel) and an equidistant
A distance along its axis. For them there runs the same
current intensity I, and this trend in the central loop has the opposite direction with respect to
turns at the ends. The end turns with radius R. If we get to
center of the spiral in the middle there is a field B ~ null, what radius should be in the main loop?

Question

Consider three circular turns flat, facing each other (parallel) and an equidistant
 A distance along its axis. For them there runs the same
 current intensity I, and this trend in the central loop has the opposite direction with respect to
 turns at the ends. The end turns with radius R. If we get to
 center of the spiral in the middle there is a field B ~ null, what radius should be in the main loop?

anonymous · Answer

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