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Question
Why is the core of a transformer made of soft iron?
Solution
The core of a transformer is made of soft iron because it has high permeability, so it provides complete linkage of the magnetic flux of the primary coil to the secondary coil. Secondly, the hysteresis loss of energy in soft iron is less.
RELATED QUESTIONS
Find the ratio of primary and secondary currents in terms of turn ratio in an ideal transformer.
The primary coil of an ideal step-up transformer has 100 turns and the transformation ratio is also 100. The input voltage and power are 220 V and 1100 W, respectively. Calculate the
(a) number of turns in secondary
(b) current in the primary
(c) a voltage across secondary
(d) current in secondary
(e) power in secondary
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(iii) Name the type of transformer.
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Long distance power transmissions
The large-scale transmission and distribution of electrical energy over long distances is done with the use of transformers. The voltage output of the generator is stepped up. It is then transmitted over long distances to an area sub-station near the consumers. There the voltage is stepped down. It is further stepped down at distributing sub-stations and utility poles before a power supply of 240 V reaches our homes.
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- Lower current implies less power loss.
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Explain why core of a transformer is always laminated.
