Q10 of 51 Page 328

Is energy produced when a transformer steps up the voltage?

No.

When a transformer steps up the voltage, the voltage increases but the current decreases in the process since the supplied power remains constant.


Now, the power is given by


where V = voltage, I = current.


Since the voltage and current increase and decrease in proportion to each other, the value of power remains constant.


Hence, energy is not produced. Energy = power x time remains constant. (Ans)


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