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Question
The resistance of filament of an electric heater is 500 Ω It is operated at 200V for 1 hour daily. Calculate the current drawn by the heater and the energy consumed in kWh, by the heater in a month of 30 days.
Solution
Given: R= 500 Ω, V = 200 volt.
Total time = t = 1 × 30h = 30h = 30 × 60 = 60 s = 108000s.
Current drawn by the heater I = `"V"/"R" = 200/500 = 0.4` A
The energy consumed (in kWh) =`("voltage" xx "Current")/100 xx "Time"`
`= (200 xx 0.4)/1000 xx 30` = 2.4 kWh.
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