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Question
If a 1200 W electric iron is used daily for 30 minutes, how much total electricity is consumed in the month of April?
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Solution
Data: P = 1200 W, t = 30 days × `"30 minutes"/"day" xx (60 "s")/("minute") = 54000 "s"` W = ?
P = `"W"/"t"`
∴ W = Pt
∴ W = 1200 W × 54000 s
= 648 × 105 J
= 6.48 × 107 J
= `(6.48 xx 10^7 "J")/(3.6 xx 10^6)` units
= 18 units
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