Question

The best material for the core of a transformer is -
(A) Stainless steel
(B) mild steel
(C) Hard steel
(D) soft iron

Answer 1

Hint: - The material for the core of a transformer should have high permeability.
- And the material for the core should have a hysteresis curve of a small area.
- And coercivity of that material should be low.

Complete step by step solution:
A transformer is a device used in the power transmission of electric energy.

The core acts as a support to the winding of the transformer, but the core should not oppose or resist the magnetic flux.
And the material of the core should have high permeability. Its hysteresis curve should have a small area and its coercivity should be very low.

And soft iron is the best for that.

So, the correct option is (D).

Note: - If any material has a smaller area in hysteresis loop. It means it has smaller hysteresis loss.
- Transformer is commonly used to increase or decrease the supply voltage without change in the frequency of AC between circuits.
- Transformer works on basic principles of electromagnetic induction and mutual induction.