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Question
Three 250 W heaters are connected in parallel to a 100 V supply, Calculate the energy supply in kWh to the three heaters in 5 hour.
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Solution

The energy supplied to heaters:
Total power consumption = 250 + 250 + 250 = 750 W.
∴ Energy supplied in kWh in 5 hours
`= ("Watt" xx "hour")/1000`
`= (750 xx 5)/1000` kWh
= 3.75 kWh.
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