Electromagnetism questions | form four Physics

Why is the iron core made of laminations instead of being in one solid piece?

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UNSOLVED

A transformer is used on the 240V a.c. supply to deliver 8A at 90 Volts to a heating coil; calculate
(i) the current in the primary winding
(ii) the power in the secondary winding
(iii) If the primary current is used to light 25 12V, 24W ray lamps what is the efficiency of the transformer?

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UNSOLVED

(a)Draw a labelled diagram of a simple d.c. motor.
(b) Explain why the coil will rotate when the current flows in it and why it will turn in a
specific direction.

(c) Why does such a motor occasionally not start to rotate when the current is switched on but will give continuous rotation after a slight push?

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UNSOLVED

What practical steps are taken in order to minimize eddy currents in the core of a
transformer?

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UNSOLVED

Is it possible to construct a transformer with 100% efficiency? Why?

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UNSOLVED