Question

A 100 W electric bulb is lighted for 3h daily and four 60 W electric bulbs are lighted for 2h daily. Calculate the units of energy consumed in a month of 30 days.

Answer 1

P = 100W = 0.1 W
t = 3 h
Energy consumed by 100 W bulb per day = 0.1×3 = 0.3 kWh
Energy consumed per day by four 60 W bulbs = 0.06×4×2 = 0.48 kWh
Total Energy consumed in a month of 30 days = (0.3 + 0.48) kWh × 30
= 0.78 × 30
= 23.40 units