MAGNETISM AND ELECTROMAGNETISM
Magnetic Materials
A substance that has the property of being attracted by or attracting the magnet is known as Magnetic Material.
Three Classes of this are
1. Paramagnetic Materials
2. Diamagnetic Materials
3. Ferromagnetic Materials
Paramagnetic Materials Example
Ferromagnetic Materials Example
Magnetic Field :
Space around the poles of a magnet is called the magnetic field, & is represented by magnetic lines of force.
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| Magnetic Field |
The force Exerted on one magnet by another, either attraction or repulsion, is known as Magnetic force.
Examples - Compass, Motor, Train Tracks & Roll Coasters
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| Magnetic Force |
First Law
Unlike Poles attract each other & like poles repel each other.
Second Law
The force between two magnetic poles
i) Directly proportional to the product of their pole strengths.
ii) Inversely proportional to the square of the distance between them.
iii) Depends on the medium in which the poles are placed.
Where,
Magnetic Strengths of Magnetic Poles = m1 & m2
Distance between two magnetic poles = r
Permeability of the medium = u
The force of attraction or repulsion between two magnetic poles = F.
Relative Permeability (ur)
The ratio of the force between two magnetic poles placed at a certain distance in the air to the force between them placed at the same distance in that medium.
Magnetic Field Strength (H)
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Relative Permeability |
Force experienced by a unit north pole placed at that point.
Represented By H.
It is a Vector Quantity.
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| Magnetic Field Strength |
Magnetic Potential
Work required to move the unit (one weber) north pole from infinity to that point against the magnetic force.
It is a Scaler Quantity,
i.e. it has magnitude only.
Magnetic Lines of Force