Q38 of 72 Page 12

Two lamps, one rated 100 W at 220 V, and the other 60 W at 220 V, are connected in parallel to a 220 V supply. What current is drawn from the supply line?

Let the current drawn from the supply be I and the individual currents drawn by each lamp be I1 and I2 respectively. Since they are connected in parallel the voltage drop 'V' across each lamp is the same, which is also equal to the supply voltage 220 V. Then current in lamp 1 I1 = = 0.4545 A Similarly current in lamp 2 I2 = = 0.2727 A Therefore the net current drawn I = I1 + I2 = 0.7272 A

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