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Question
Five electric fans of 120 watts each are used for 4 hours. Calculate the electrical energy consumed in kilowatt-hours.
Solution
Power of each fan,
(P) = 120 W
= 0.12 kW
Time duration, (t) = 4 hr
Now, we can calculate the electrical energy consumed as,
Energy consumed = Power × Time
So,
Energy consumed by 1 fan
= 0.12 × 4 kWh
= 0.48 kWh
So, the energy consumed by 5 fans is,
Energy consumed by 5 fan
= (0.48) (5) kWh
= 2.4 kWh
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