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Question
A bulb of 40 W is used for 12.5 h each day for 30 days. Calculate the electrical energy consumed.
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Solution
Energy consumed per day , E = P × t
= 40 × 12.5
= 500 Wh
Energy consumed for 30 days
E = 500 × 30 = 15000 Wh = 15 kWh.
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