Question 55
MediumOriginal questionA 1,500 W geyser runs for 2 hours every day. How many units (kWh) of electricity does it use in 30 days?
Show the answer and explanation
CorrectNot quiteAnswer C
Correct answer: C
Explanation
Power = 1,500 W = 1.5 kW.
Energy per day = 1.5 × 2 = 3 kWh; for 30 days = 3 × 30 = 90 kWh.
Worth noting
90,000 keeps the power in watts: that is 90,000 watt-hours, which is 90 kWh. 3 kWh is one day only.
- Concept
- Energy consumed in kilowatt-hours
- Typical timeTypical
- 60 s
- Your timeYours
- —
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