In an experiment, a wire is positioned above a compass needle, as shown. An electric current is then switched on in the wire, and the compass needle moves away from its original position. Which row gives the reason for this and then states what occurs when the current is reversed?
- Athere is a magnetic field inside the wire; the compass needle deflects in the opposite direction
- Bthere is a magnetic field inside the wire; there is no effect on the compass needle
- Cthere is a magnetic field around the wire; the compass needle deflects in the opposite direction
- Dthere is a magnetic field around the wire; there is no effect on the compass needle