Peter and Paul East and West North and South Helmholtz and Tesla
One which attracts you strongly One which attracts plants strongly A region around a magnet where magnetic materials feel a force A region of space
Iron Copper Purified and drawn oxygen free copper Carbon dioxide
Always attract Always repel Sometimes repel Neither attract nor repel
Always cross each other Sometimes cross each other Never cross each other Are painted blue and red
Doubles Quadruples Gets weaker Stays the same
Always point from east to west Always point from west to east Always point from north to south Always point from south to north
