A household refrigerator consumes electrical energy at the rate of 200 W. lf electricity costs 5 k per kWh, calculate the cost of operating the appliance fo...

A household refrigerator consumes electrical energy at the rate of 200 W. lf electricity costs 5 k per kWh, calculate the cost of operating the appliance for 30 days.

Answer Details

To calculate the cost of operating the refrigerator for 30 days, we need to determine the total energy consumed by the refrigerator in that time period. The energy consumed by an electrical appliance is given by the product of its power and the time for which it is operated. Here, the power of the refrigerator is 200 W, and the time for which it is operated is 30 days. However, we need to convert the time to hours since the power is given in watts, which is a unit of power per unit time, usually measured in seconds. One day has 24 hours, so 30 days have 30 x 24 = 720 hours. Therefore, the total energy consumed by the refrigerator in 30 days is: Energy = Power x Time Energy = 200 W x 720 hours Energy = 144000 Wh We now need to convert this energy to kilowatt-hours (kWh) since the cost of electricity is given in k per kWh. To do this, we divide the energy by 1000: Energy = 144000 Wh = 144 kWh The cost of electricity is 5 k per kWh, so the cost of operating the refrigerator for 30 days is: Cost = Energy x Cost per kWh Cost = 144 kWh x 5 k/kWh Cost = 720 kobo or N7.20 Therefore, the correct answer is option A) N7.20.