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The core of a transformer is laminated because :-
A
Energy losses due to eddy currents may be minimised
B
The weight of the transformer may be reduced
C
Rusting of the core may be prevented
D
Ratio of voltage in primary and secondary may be increased
Detailed Solution
The alternating magnetic flux in the iron core of a transformer induces circulating currents in the body of the core, called eddy currents.
These currents heat up the core ($I^2R$ loss) and waste energy.
To reduce them, the core is made of thin sheets (laminations) of soft iron, insulated from one another by a layer of varnish, instead of one solid block.
The laminations break the paths of the eddy currents and increase the resistance offered to them, so the eddy currents and the heat produced become very small.
Lamination does not change the weight appreciably, does not prevent rusting and does not affect the voltage ratio, which depends only on the turns ratio.
So the core is laminated so that energy losses due to eddy currents may be minimised.
These currents heat up the core ($I^2R$ loss) and waste energy.
To reduce them, the core is made of thin sheets (laminations) of soft iron, insulated from one another by a layer of varnish, instead of one solid block.
The laminations break the paths of the eddy currents and increase the resistance offered to them, so the eddy currents and the heat produced become very small.
Lamination does not change the weight appreciably, does not prevent rusting and does not affect the voltage ratio, which depends only on the turns ratio.
So the core is laminated so that energy losses due to eddy currents may be minimised.