MCQ
If the magnetizing field on a ferromagnetic material is increased, its permeability
- ✓decreased
- Bincreased
- Cis unaffected
- Dmay be increased or decreased
✓
Answer
Correct option: A.
decreased
a
(a)
(a)
The magnetic permeability of a substance is defined as
$\mu=\frac{B}{H}$
where $B$ is the established magnetic field inside the material, $H$ is the applied external magnetic field.
When the external applied magnetic field $H$ is increased, the established magnetic field for a ferromagnetic material remains the same. Thus the magnetic permeability decreases.
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