Five bulbs each having 100 W power are used for 4h,a heater having 1500 W power is used for 2 h and an electric iron of power 1000 W is used for 5 h.
(i) Calculate the total energy consumed by them,
(ii) Convert this energy into joules.
(i) Energy consumed by five bulbs =5 x 100 x 4 / 1000 = 2 units
Energy consumed by 1 heater =1500 x 2 /1000 = 3 units
Energy consumed by electric iron = 1000 x 5 / 1000 = 5 units
Total energy consumed by them = (2 + 3 + 5)
= 10 units
(ii) 1 unit or kWh =3.6x ${{10}^{6}}$ J
10 units = 3.6 x10s X10J = 3.6 x ${{10}^{7}}$ J