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In a transformer, number of turns in the primary coil are 140 and that in the secondary coil are 280. If current in primary coil is 4 A, then that in the secondary coil is
- 4 A
- 2 A
- 6 A
- 10 A
Correct answer: 2 A
Solution
In a transformer, the relationship between the number of turns and the currents in the primary and secondary coils is inversely proportional. Since the secondary coil has twice the number of turns as the primary, the current in the secondary will be half that of the primary, resulting in 2 A.
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