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3 years ago

How much does it cost to operate a 90 W light bulb for one day if the cost per kilowatt-hour is $0.08

Physics

1 answer:

horrorfan [7]3 years ago

7 0

Answer:

$ 0.17

Explanation:

From the question given above, the following data were obtained:

Power (P) = 90 Watts

Time (t) = 1 day

Cost per KWh = $ 0.08

Cost of operation =?

Next, we shall convert 90 W to KW. This can be obtained as follow:

1000 W = 1 KW

Therefore,

90 W = 90 W × 1 KW / 1000 W

90 W = 0.09 KW

Next, we shall express 1 day in hour. This is shown below:

1 day = 24 hours

Next, we shall determine the energy consumption. This can be obtained as follow:

Power (P) = 0.09 KW

Time (t) = 24 h

Energy (E) =?

E = Pt

E = 0.09 × 24

E = 2.16 KWh

Finally, we shall determine the cost of operation. This can be obtained as follow:

Energy (E) = 2.16 KWh

Cost per KWh = $ 0.08

Cost of operation =?

Cost of operation = Energy × Cost per KWh

Cost of operation = 2.16 × 0.08

Cost of operation = $ 0.17

Thus, the cost of operating the light bulb for one day is $ 0.17

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