Two wires parallel to each other and seperated by a distance d carry different currents; they exert a force with magnitude F on each other.
(a) The wires carry current in the same direction. If the current carried by both wires is quadrupled and the distance between the wires is quintupled, then what will the force's magnitude be (as a multiple of F) and will it be repulsive or attractive?
(b) The wires carry current in opposite directions. If the current carried by one of the wires is quadrupled and the distance between the wires is quadrupled, then what will the force's magnitude be (as a multiple of F) and will it be repulsive or attractive?