A 60 W load is connected to the secondary of a transformer whose primary draws line voltage. If a current of 0.54 A flows in the load, what is the current in the primary coil? Comment on the type of transformer being used.



Given:
Power in the secondary coil: PS = 60 W
Current through the secondary coil: IS = 0.54 A
Voltage in the primary coil: Line voltage = VP = 220 V
Formula used:
Power is given as
P= VI
Where V is the voltage and I is the current flowing.
Thus

Here, VS is the Voltage in the secondary coil, PS is the power of the secondary coil and IS is the current through the secondary coil

VS = 111.11 V
Since VS < VP, transformer is a step down transformer.
We know that proportions



Hence current through the primary coil is 0.272 A.


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