1. Each magnetic line of force forms a closed loop.
2. No two magnetic lines of force intersect each other.
3. Where the magnetic lines of force are close together, the magnetic field is strong and where they are well spaced out, the field is weak.
4. Magnetic lines of force contract longitudinally and widen laterally.
5. Magnetic lines of force are always ready to pass through magnetic materials like iron and preference to pass through non-magnetic material like air.
Symbol of magnetic flux is ɸ
The magnetic flux is named after Willem Weber the founder of the electrical system of measurement.
The total number of magnetic lines of force produced by a magnetic source is called magnetic flux.
One weber = 10^8 magnetic lines
One milli-weber = 10^-3 x 10^8 = 1,00,000 magnetic lines
One micro-weber = 10^-6 x 10 ^8 = 100 magnetic lines
(i) When the plane of the coil perpendicular to the flux direction maximum flux will pass through the coil.
Magnetic flux = B A Wb [A = area in m^2 normal to flux]
(ii) When the plane of the coil is inclined at an angle θ to the flux direction then flux through the coil.
Magnetic flux = B A sinθ Wb
(iii) When the plane of the coil is parallel to the flux direction θ = 0 so that no flux will pass through the coil.
Magnetic flux = 0 [since, θ=0, Sin0 = 0]
Flux density (B) in soft iron is much greater than it is in air.
B is in soft iron will be 8000 times the flux density in air.
Due to the high relative permeability of magnetic materials iron, steel and other magnetic alloys widely used for the cores of all electromagnetic equipment.
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