This logic puzzle was published in Martin Gardner's column in the Scientific American. You are in a room with no metal objects except for two iron rods. Only one of them is a magnet. How can you identify which one is a magnet?
Magnet will always positions itself in S-N way... this property will be helpful to identify magnet
Place the rod on the ground with different position. If the rod always points in one particular direction irrespective of its position, than that rod is a magnet. As magnetic rod always points in North-South direction.
