Permanent Magnets and Electromagnets
Substances which at room temperature retain their ferromagnetic property for a long period of time are called permanent magnets. Permanent magnets can be made...
Ferromagnetic Substances
Ferromagnetic substances are those which develop strong magnetization in the direction of the magnetizing field. They are strongly attracted by magnets and tend to...
Diamagnetic Substance
Diamagnetic substances are those which develop feeble magnetization in the opposite direction of the magnetizing field. Such substances are feebly repelied by magnets and...
Paramagnetic Substance
Paramagnetic substances are those which develop feeble magnetization in the direction of the magnetizing field. Such substances are feebly attracted by magnets and tend...
Earth’s Magnetic Field and Magnetic Elements
A freely suspended magnetic needle at a point on Earth comes to rest approximately along the geographical north-south direction. This shows that the Earth...
The Magnetic Field Lines
The magnetic field lines are a visual and intuitive realization of the magnetic field. Electric field lines of an electric dipole are also displayed...
Bar Magnet as an Equivalent Solenoid
To demonstrate the similarity of a current carrying solenoid to a bar magnet, let us calculate axial field of a finite solenoid carrying current.
Consider:...
Torque on a Bar Magnet Placed in a Uniform Magnetic Field
Consider a bar magnet NS of length 2l and pole strength m placed in a uniform magnetic field of induction B at an angle θ...
Magnetic Field Intensity Due to a Magnetic Dipole
Magnetic field intensity at a general point having polar coordinates (r,θ) due to a short magnet is given by
Special Cases:
At...
Magnetic Dipole Moment of a Revolving Electron
According to Neil Bohr’s atom model, the negatively charged electron is revolving around a positively charged nucleus in a circular orbit of radius r....