As one conductor AB moves down through the field, the other CD moves up and the induced E.M.FS. will be such that A is +ve relative to B and C is +ve relative to D. The induced current, if allowed to flow, would be as shown by the arrows and since it is from terminal Y to terminal X through the external circuit, Y is +ve with respect to X. It would be well for the student at this point to try the right-hand rule for himself and satisfy himself as to the polarity of the terminals for the half-revolution being considered. Itshould be noted that the right-hand rule as described, can be applied here to conductor AB, the condition It should be noted that the right-hand rule as described, can be applied here to conductor AB, the condition being that AB is moving from the top vertical position round past the centre of the magnet pole and then onto the bottom vertical position. The position where it moves past the pole at right angles is of particular importance, being a condition of maximum E.M.F.