An apparatus has two batteries in a row (negative-positive negative-positive is how the batteries go..the negative part is above the positive one in two consecutive batteries.). There is a switch after the two batteries, the wire holding the batteries is conected to conducting rails on both sides and on the rails is a conducting bar free to slide. The question is what happens when the switch closes. I figure when the switch closes it makes a complete circuit, the current can keep flowing through the rails and the bar. The bar i believe will move but unsure in what direction. Would like some clarification to confirm that this is what will indeed happen.