An electric refrigerator rated 400 W operates 8 hour/day. What is the cost of the energy to operate it for 30 days at Rs 3.00 per kW h?

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  1. Class 10
  2. Chapter 12 Class 10 - Electricity (Term 2)

Transcript

Example 12.13 An electric refrigerator rated 400 W operates 8 hour/day. What is the cost of the energy to operate it for 30 days at Rs 3.00 per kW h? Power of the fridge = P = 400 W Time taken to consume (per day) = t = 8 hours To find cost, we need to find energy consumed in 30 days We know that, Power = (πΈπ‘›π‘’π‘Ÿπ‘”π‘¦ π‘π‘œπ‘›π‘ π‘’π‘šπ‘’π‘‘)/(π‘‡π‘–π‘šπ‘’ π‘‘π‘Žπ‘˜π‘’π‘› ) Energy consumed = Power Γ— Time taken = P Γ— t = 400 Γ— 8 = 3200 Wh = 3200/1000 kWh = 3.2 kWh Finding energy consumed in 30 days Energy consumed in 1 day = 3.2 kWh Energy consumed in 30 day = 30 Γ— 3.2 kWh = 30 Γ— 32/10 = 3 Γ— 32 = 96 kWh Finding cost Cost of 1 kWh = Rs 3 Cost of 92 kWh = 96 Γ— 3 = Rs 288 Cost of energy consumption is Rs 288

About the Author

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CA Maninder Singh
CA Maninder Singh is a Chartered Accountant for the past 11 years and a teacher from the past 11 years. He teaches Science, Accounts and English at Teachoo