When a bar magnet is cut into two halves repel each other. Why? What becomes of the original north and south poles of that magnet?
When a bar magnet is cut into two halves, each half becomes a separate magnet with its own poles. This is because the magnetic field is a result of the alignment of magnetic domains within the material.
In a bar magnet, these domains are aligned in a specific pattern, causing the north and south poles to form. When the magnet is cut, the domains near the cut surface are disrupted, causing them to realign in order to minimize the energy in the system. As a result, each piece of the magnet forms its own magnetic field and poles.
Now, you might wonder why the two halves repel each other. This can be explained by considering the nature of magnetic fields. Like poles repel, while opposite poles attract. So, when the bar magnet is cut, the two halves essentially become two separate magnets with the same poles facing each other. Hence, they repel each other.
To verify this explanation, you can conduct a simple experiment. Take a bar magnet and a small compass. Observe the direction in which the compass needle aligns with the magnet. Then, carefully cut the magnet into two halves. Bring the compass needle close to each half separately. You will notice that each half behaves like an individual magnet, with its own poles. Additionally, when you bring the compass near the cut surface, you will observe that the two halves repel each other, confirming the repulsive nature of like poles.
In summary, when a bar magnet is cut into two halves, each half becomes a separate magnet with its own poles. The repulsion between the two halves occurs because the like poles are facing each other.