Question

In a house there are 6 bulbs of 100 W each used for 4 hours a day, 4 bulbs of 60 W each used for 8 hours a day, an immersion heater of 2.5 kW used for 1 hour per day, and an electric iron of 800 W used for 2 hours per day. Calculate the cost of monthly electric bill for the month of April at the rate of 80 p per unit.

Answer 1

Energy consumed by 6 bulbs per day = `6 xx 100/1000 xx 4 = 2.4  "kWh"`

Energy consumed by 4 bulbs per day = `4 xx 60/1000 xx 8 = 1.92  "kWh"`

Energy consumed by immersion heater per day = 2.5 x I= 2.5 kWh

Energy consumed by electric iron per day = `800/1000 xx 2 = 1.6 "kWh"`

Total energy consumed in I day= 2.4 + 1.92 + 2.5 + 1.6 = 8.42 kWh

Total energy consumed in the month of April (30 days) = 8.42 x 30 = 252.6 kWh

Electric bill for the month of April= 252.6 x 0.8 =Rs. 202.08