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Question
Three 250 W heaters are connected in parallel to a 100 V supply, Calculate total current taken from the supply.
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Solution

Total current drawn from the supply
I = I1 + I2 + I3
Since each heater is of 250 W.
Therefore, I1 = I2 = I3
and total current I = 3I,
or I = `3 (250/100)` = 3 (2.5 A) = 7.5 A
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