Question

what are magnetic field lines? How is the direction of magnetic field at a point in a magnetic field determined using field lines?​

Answer 1

Imaginary lines that represent the direction of magnetic field are called magnetic field lines

Right hand thumb rule determines the direction of magnetic field

Hope it will help you

Answer 2

Magnetic field is represented by the field lines. They are imaginary lines drawn in a magnetic field along a unit North magnetic pole moves. Magnetic field lines are called as magnetic lines of force.