A. Low Reluctance path to the main flux
B. High Reluctance path to the main flux
C. Low Resistance path to the main flux
D. High conductivity path to the main flux
Answer: A. Low Reluctance
Explanation:
In transformers, the two coils are wound onto the same iron core. The purpose of the iron core is to channel the magnetic flux generated by the current flowing around the primary coil so that as much of it as possible also links the secondary coil.
The iron core is also used to decrease the magnitude of magnetizing current.
The iron core in a transformer provides a Low Reluctance path to the main flux.
transformers use a principle of mutual induction. One coil energized with an alternating voltage produces a current flow that creates an alternating magnetic field.
Another coil located close by will have an alternating voltage induced in it.
The two coils are linked by magnetism
Air is not a good conductor of magnetism.
Iron and some other composite materials like ferrite are vastly much better conductors of magnetism.
So to improve the efficiency of power transformers a laminated iron core is used in low-frequency transformers at 50 and 60 hz.
A ferrite core can be used for mains frequency transformers but is more commonly used in transformers that operate at high frequencies.
Some very high-frequency transformers may use an air core.
Ferrite cores can be molded into intricate shapes that is much more difficult to do with laminated iron cores.
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