[Illustration: Fig. 14i.]

Having thus demonstrated the practical identity of a loop and a
magnet, we proceed to examine the effects produced by loops on
straight wires.

If the loop is placed with a straight wire in its plane along one
edge, there will be attraction or repulsion, according to the
direction of the two currents, Figs. 20 and 20a, which are obviously
the same as Figs. 8 and 8a.

[Illustration: Fig. 20.]

[Illustration: Fig. 20a.]

[Illustration: Fig. 20b.]

[Illustration: Fig. 20c.]

If the wire is placed parallel to the plane of the loop and to one
side, Figs. 20b and 20c, there will be rotation (same as Figs.
4b and 4c).

If the loop is horizontal and the wire vertical and on one side, the
Figs. 20d, 20e are the same as 4d and 4e.

If the loop is horizontal and the wire vertical and axial, 20f and
20g, there will be rotation, and the figures are mere duplicates of
4g and 4h.