Question

a house as one bulb of 100w used for 10 hours a day the cost of electric energy used by the bulb in 30 days @ruppees 3 per kwh is

Answer 1

As we know that

Energy = Power x Time

So the energy consumed

by the 0.1KW bulb for 10 hrs = 0.1x10 =} 1Kwh

So the energy consumed in one day = 1Kwh

So the energy consumed in 30 days = 30 x 1Kwh=} 30Kwh

Hence the cost of consumption of energy for 30 days @ Rs.3 = 30Kwh x 3 = Rs.90

Hope it Helps