1. Which way would a compass point if you were at Earth's north magnetic pole?
2. Can a constant magnetic field set a proton at rest into motion? Explain your answer.
3. Will a nail be attracted to either pole of a magnet? Explain what is happening inside the nail when it is placed near the magnet.
4. Why do charged particles from outer space, called cosmic rays, strike Earth more frequently at the poles than at the equator?