A single-phase, 230 V, 50 Hz ac mains fed step down transformer (4:1) is supplying power to a half-wave

A single-phase, 230 V, 50 Hz ac mains fed step down transformer (4:1) is supplying power to a half-wave uncontrolled ac-dc converter used for charging a battery (12 V dc) with the series current limiting resistor being 19.04 Ohm. The charging current is 

(A) 2.43 A (B) 1.65 A (C) 1.22 A (D) 1.0 A
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Answer :

A single-phase, 230 V, 50 Hz ac mains fed step down transformer (4:1) is supplying power to a half-wave uncontrolled ac-dc converter used for charging a battery (12 V dc) with the series current limiting resistor being 19.04 Ohm. The charging current is 1.0 A

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