MAGNET: The substance which attracts small pieces of iron and points toward the north and south direction when suspended freely is called a magnet.
The material which is attracted by the magnet is called magnetic material, For example, iron, cobalt, nickel, and many compounds of these materials. These are called magnetic materials.
The study of the properties associated with a magnet is called magnetism.
The study of the properties of the magnetic field associated with the current flowing through the conductor.
MAGNETIC LINES OF FORCE
The path along which an isolated north pole of a magnet moves in the magnetic field is called the magnetic line of force.
(i) The magnetic lines of force are imaginary.
(ii) These lines start from the N pole and end at the S pole.
(iii) These lines are crowded near the poles and widely spaced in the middle around
(iv) These lines do not intersect one another.
(v) Due to these lines magnetic field is stronger near the poles and becomes weak in the middle around the magnet because these are widely spaced there.
(vi) These lines form concentric circles around a current-carrying wire.