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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 = 1.2 kW
t = 30 minutes = `30/60` = 0.5 hr
To find: W = ?
Formula: P = `W/t`
∴ W = Pt
∴ W = 1.2 × 0.5
= 0.6 kWh
April has 30 days.
Total electricity consumed in April:
= 0.60 × 30
= 18 kWh
= 18 units
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