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2 years ago

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A heater marked 2000W/3000W is switched on for 4 hours. For the first hour it is on the highest setting and for the last 3 hours

it is on the lowest setting
1.1 How much energy does it transfer to the room in kWh (9kWh)

1 answer:

Leni [432]2 years ago

3 0

Answer:

9 kW-hr

Explanation:

3000 W = 3 kW for 1 hr = <u>3 kW - hr </u>

2000 W = 2 kW for 3 hr = <u> 6 kW -hr</u>

<u />

total power = <u> 3 + 6 = 9 kW-hr</u>

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