Question

An electric refrigerator rated 400 W is used for 8 hours a day. An electric iron box rated 750 W is used for 2 hours a day. Calculate the cost of using these appliances for 30 days, if the cost of 1 kWh is RS.3/-

Answer 1

Power of refrigerator=400W

1kw=1000W

power of refrigerator=400/1000

=0.4kw

Time=8h

power=electrical energy consumed/time

Electrical energy consumed=power ×time

E=0.4×8

E=3.2kwh

electrical energy consumed for 1day=3.2kwh

electrical energy consumed for 30 days=3.2×30

=96kwh

cost of 1kwh=3/-

cost of 96kwh=96×3

=288/-

so for elecric iron repeat the same