Question

Four bulbs of 25 W each operate 10 hours daily.The total monthly energy bill will be,if unit price is Rs.10?​

Answer 1

Bulb Rating = 40 W = .04 kW

Bulb illuminates for = 10hrs/day

Bulb consumes units( kWH)/day= .04×10= .4 kWH/ day = .4 units/ day

In 30 days = .4×30 = 12 units

1 unit cost = 250/-

12 units cost = 250×12 = 3000/-

Answer 2

Answer:

Rs:300

Explanation:

Energy= 25 watt= 0.025kwatt

Power= E/t= 0.025/10= 0.25kwatt/hr

For 30 days, => 0.25×30=7.5kwatt/hr

cost of one bulb= 7.5×10= Rs 75

cost of four bulbs= 75×4= Rs 300