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Why is the iron core of a transformer made of thin laminated sheets?
- To make it lighter in weight
- To make it mechanically robust and strong
- To increase the secondary voltage
- To reduce energy loss caused by eddy currents
Correct answer: To reduce energy loss caused by eddy currents
Solution
A solid core would allow large eddy currents induced by the changing flux, dissipating energy as heat. Laminating the core into thin, mutually insulated sheets confines and reduces these circulating currents, cutting eddy-current power loss.
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