A magnet is an object that is usually made of iron or steel. Magnets come in different shapes and sizes. Some common types are bar magnets, rod magnets, U-shaped magnets, horseshoe magnets, button magnets, and ring magnets.
Magnets can interact with some objects. Magnets attract objects made of magnetic materials. Magnetic materials include iron and steel. Examples: iron nails, steel pins, steel paperclips.
Objects that are not attracted to magnets are made of non-magnetic materials. Non-magnetic materials include ceramic, glass, plastic, rubber and wood. Metals such as aluminium and copper are also non-magnetic.
⚠️ Not all metals are magnetic! Aluminium and copper are metals but they are non-magnetic. 并非所有金属都有磁性！铝和铜是金属，但它们是非磁性的。
🔴🔵 Poles of a magnet · 磁铁的磁极
A magnet has two poles: a North pole and a South pole. The poles are where the attraction is the strongest. When a bar magnet is held over steel clips, the clips are attracted most strongly to the two ends (poles).