A lamp rated 100W, 240V is lit for 5hours. Calculate the cost of lighting the lamp if 1kWh of electrical energy cost N5.
Question 1 Report
A lamp rated 100W, 240V is lit for 5hours. Calculate the cost of lighting the lamp if 1kWh of electrical energy cost N5.
Answer Details
To calculate the cost of lighting the lamp, we need to determine the amount of energy consumed by the lamp, which is given by:
Energy = Power x Time
Where power is given in Watts, time is given in hours, and energy is given in kilowatt-hours (kWh).
First, we need to convert the power rating of the lamp from 100W to kW:
Power = 100W / 1000 = 0.1 kW
Next, we can calculate the energy consumed by the lamp during the 5 hours it was lit:
Energy = Power x Time = 0.1 kW x 5 hours = 0.5 kWh
Finally, we can calculate the cost of lighting the lamp based on the cost of 1 kWh of electrical energy, which is given as N5:
Cost = Energy x Cost per kWh = 0.5 kWh x N5/kWh = N2.50
Therefore, the cost of lighting the lamp is N2.50.
Option (A) N2.50 is the correct answer.
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