Question

26. Find the cost of running the following devices in the month of February 2021 if the rate of 1 unit of
electricity is 9.
(i) Electric heater of 1 KW for 5 hours daily.
(ii) Electric refrigerator of 400 W for 10 hours daily.​

Answer 1

Explanation:

(i) Energy consumed(for ele. heater) = 1×5 kW-h

= 5 unit per

day

For month February(total energy consumed)

= 28×5

= 140 units

so, total cost will be 9×140= Rs 1260.

(ii) Energy consumed(for ele. refrigerator)

=> (400/1000)×10 = 4 kW-h or 4 units per day.

For month February(total energy consumed)

=> 28×4= 112.

so, total cost will be 9×112= Rs 1008.