Magnetic Dipole and Magnetic Dipole Moment
A magnetic dipole is formed by placing a magnetic north pole and south pole closer together, where the product of the magnetic pole charge and distance is constant. Andre-Marie Ampere gave the idea that a current loop can act as a magnetic dipole. This phenomenon is explained by Ampere with the help of the circular movement of current through the wire. It is similar to the magnetic dipole with the magnetic field line straight at the center of the loop. If the current flows in a circular loop inside a magnetic field it behaves as a magnetic dipole. When an electron rotates around the positively charged nuclei, it forms a magnetic dipole. The direction of the magnetic field lines is determined by the direction of current flow in the wired loop.
In a magnetic dipole, two opposite magnetic charges (bar magnet) are kept at a very short distance. Magnetic Dipole Moment is defined as the ability of a magnetic dipole to align itself with the magnetic field outside. The magnetic dipole moment is defined as the maximum amount of torque caused by magnetic force on a dipole that arises per unit value of the surrounding magnetic field in a vacuum. It is a vector quantity and its direction is from the north pole to the south pole. Its SI unit is Ampere-meter2 and its cgs unit is ergs per gauss.
The torque of the dipole can be written as,
τ = M × B
where,
τ is the torque acting on the dipole
M is the magnetic moment
B is the outside magnetic field
A magnetic dipole is the presence of both poles of a magnet, this creates a magnetic field. For example, when a bar magnet is broken into pieces, each piece will act as a magnetic dipole individually, and every piece will carry a north and a south pole.
Current Loop as a Magnetic Dipole
When a charge move it generates an electric field and the rate of flow of charge is the current in the electric field. This is the basic concept in Electrostatics. The magnetic effect of electric current is the other important concept related to moving electric charges. Magnetism is generated due to the flow of current. Magnetic fields exert force on the moving charges and at the same time on other magnets, all of which have moving charges. When the charges are stationary, their magnetic field doesn’t affect the magnet but when charges move, they produce magnetic fields that exert force on other magnets.
The movement of charges generates magnetism around a conductor. Generally, magnetism is a property shown by magnets and produced by moving charges, which results in objects being attracted or pushed away.