Final answer:
To identify the poles of a magnet without a compass, use another magnet with known poles and observe the attraction or repulsion. The Earth's magnetic field also helps identify poles as a magnet's north pole will orient towards the geographic North Pole.
Step-by-step explanation:
To identify the north and south poles of a magnet without a compass, you can use the interaction between two magnets. When two magnets are brought close together, like poles will repel each other, and unlike poles will attract. For example, if you have a magnet with known poles, you can bring its north pole near the unidentified magnet. If there is a repulsion, the pole you brought it near to is also a north pole. Conversely, if there is an attraction between the two poles, the unidentified pole is a south pole.
An acclaimed experiment by Hans Oersted in 1819 revealed that electric currents generate magnetic fields, which led to further understanding of magnetic forces. Interestingly, the Earth acts like a giant bar magnet with its magnetic field, which a compass aligns with, suggesting that what we consider the magnetic north pole is actually the magnetic south pole of Earth, due to magnetic field lines pointing from north to south. This fact serves as a foundation for the concept that magnet's north pole will always orient toward the Earth's geographic North Pole.