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A 100W light bulb is left on for 5.5 hours. How many kilowatt-hours of energy is used?

User Isabsent
by
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2 Answers

0 votes

Answer:

0.55kwh

Step-by-step explanation:

watt to kilowatt

100/1000 = 0.1kw

kwh = kilowatt × hour

= 0.1kw × 5.5 hrs

= 0.55kwh

User Alec Matusis
by
5.5k points
4 votes

Answer:

Step-by-step explanation:

Well a unit can also be written as a kW-h.

What does kW-h mean?

Kilo Watt - Hour.

Watt-hours are nothing but number of watts multiplied by number of hours.

No. Of Watts = 100

No. Of hours = 5.5

Therefore,

No. Of Watt-hours = 550

Now just like a 550 grams = 0.55 kilo gram

550 W-h = .55 kilo W-h = 0.55 kW-h

But we mentioned earlier that 1 unit is equivalent to 1 kW-h.

Therefore the answer to your question is 0.55.

The bulb consumes 0.55 unit.

User Abid Rahman K
by
5.0k points