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Question
If an electric iron of 1200 W is used for 30 minutes every day, find electric energy consumed in the month of April.
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Solution
Power of electric iron, P = 1200 W Time for which it is used in one day, t = 30 min
= 30 × 60 s
= 1800 s
Energy consumed in one day = P × t
= 1200 W × 1800 s
= 2.16 × 106 J
As there are 30 days in April, so energy consumed in the month of April = 2.16 × 106 × 30 J
= 6.48 × 107 J
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