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

$ 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

this means that the temperature of both substances will be equal

see the picture for the vector

the magnitude of the vector by pythagorean theorem

r = √( (-10)^2 + (3)^2 ) = √109

magnitude = √109 units

the direction angle between vector and x-axis is

tan^(-1)(3/10) = 16.699

so the direction is approximately 16.7 degrees north of west