Explain how an electric transformer changes the voltage of the electric current. Why does a transformer work only with alternating current?

Transformer work only on ac supply because an alternating current is needed to create a changing magnetic field.

A transformer is a static device that converts voltage or current from one level to another level.

Transformer work only on ac supply because an alternating current is needed to create a changing magnetic field. A changing magnetic field also induces a changing voltage in a coil. This is the basis of how a transformer works.

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An electric transformer is a device that uses electromagnetic induction to change the voltage of electric current. ... When alternating current passes through coil P, it magnetizes the iron core. Because the current is alternating, the magnetic field of the iron core keeps reversing.

A transformer needs an alternating current that will create a changing magnetic field.

answer:

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explanation:

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