Why does a compass needle get deflected when brought near a bar magnet?
A compass needle gets deflected when brought near a bar magnet because the compass needle is, in fact, a small bar magnet. It has a north pole and a south pole.
A magnetic field exists in the region surrounding a bar magnet, in which the force of the magnet can be detected. When the compass needle is brought near the bar magnet, it experiences this magnetic force.
Since like poles repel, while unlike poles of magnets attract each other, the compass needle gets deflected. The south pole of the needle points towards the north pole of the magnet, and the north pole of the compass is directed away from the north pole of the magnet.
Explanation
The textbook states that a compass needle is a small bar magnet with north and south poles. When brought near a bar magnet, the compass needle experiences the magnetic field and the force of the magnet. Due to the fundamental principle that like poles repel and unlike poles attract, the compass needle deflects and aligns itself according to the magnetic field lines of the bar magnet.
Solution Steps
Step 1: Identify that a compass needle is a small bar magnet with north and south poles.
Step 2: Understand that a magnetic field exists around a bar magnet where the force can be detected.
Step 3: Apply the principle that like poles repel and unlike poles attract to explain the deflection.