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Question
Three heaters each rated 250 W, 100 V are connected in parallel to a 100 V supply of the energy supplied in kWh to the three heaters in 5 hours.
Solution
Given ,
Power , P = 250 W
Voltage , V = 100 V
Time for which energy is supplied , t = 5 h
As , Energy E = P × t
E = 250 × 5 = 1250 Wh
or E = 1.25 kWh
Energy for three heaters = 3 × 1.25 = 3.75 kWh
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