The diagram that best illustrates the magnetic field near a wire that carries an electron current into the plane of the paper is: a. O b. O d. Navigational compasses are not used in the far north because Earth's magnetic field lines: O a. do not exist in the far north O b. point out into space in the far north O c. point down to the Earth in the far north O d. run parallel to the Earth's surface in the far north A ferromagnetic nail is suspended by a string from a support. When a magnet is brought near the nail, it is observed that the nail will rotate toward the magnet. The best explanation for the observed behavior is: O a. the nail is magnetized by induction O b. the nail is charged by induction, O c. the nail is charged by conduction O d. the nail is attracted by the gravitational field of the magnet An electric current in a copper wire produces: a. only an electric field O b. only a magnetic field Oc an electric and magnetic field Od. a light electric, and magnetic field