Question

magnetic field lines are closed and continuous curves.explain​

Answer 1

Magnetic field lines represent continuous curves that originate at the north pole of a magnet and end at the south pole. Inside the magnet they travel from the south pole to the north pole.

As isolated magnetic poles or monoploes do not exist; the smallest source of magnetic field is a magnetic dipole or a current loop. North and south (N-S) always come togheter.

Therefore, the magnetic field lines are continuous and form closed loops.

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