An air gap is usually inserted in magnetic circuits to Prevent saturation.
More than 100 or 1000
The relative permeability of a ferromagnetic material is More than 100 or 1000.
The unit of magnetic flux is Weber.
Lower their power efficiency
Permanent magnets are normally made of Alnico alloys.
Energy stored by a coil is doubled when its current is increased by 41.4 percent.
High permeability, Low hysteresis loss
Those magnetic materials are best suited for making armature and transformer cores should have High permeability, Low hysteresis loss.
At the start of the current flow
The rate of rise of current through an inductive coil is maximum At the start of the current flow.
Time constant remains unchanged
When both the inductance and resistance of the coil are doubled the value of Time constant remains unchanged.
A material for good magnetic memory should have High retentivity.
It's high retentivity
In a magnetic material hysteresis loss takes place primarily due to It's high retentivity.
High retentivity, high Coercivity
Those materials are well suited for making permanent magnets should have High retentivity, high Coercivity.
If the area of hysteresis loop of a material is large, the hysteresis loss in this material will be Large.
It has good residual magnetism
Hard steel is suitable for making permanent magnets because It has good residual magnetism.
Silicon steel is used in electrical machines because it has Low hysteresis.
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