Magnetic lines of force always originate from the North Pole and end at its the South Pole.
Magnetic lines of force are defined as the curved lines which are used for representing the magnetic field. These lines do not exist but are imaginary lines through the pattern of the magnetic field is explained.
These imaginary lines are assumed to originate from the north pole and reach to the south pole by travelling inside the magnet thereby completing the loop.
These imaginary lines have properties such as they do not interact with each other. They don’t have a start and endpoint.
The number of magnetic lines passing through a unit area is known as magnetic induction while the number of magnetic lines of force passing through any area is known as magnetic flux.