question_answer

  Five bulbs each having 100 W power are used for 4 h, a heater having 1500 W power is used for 2 h and an electric iron of power 1000 W is used for 5 h. (a) Calculate the total energy consumed by them. (b) Convert this energy into joules.

Answer:

   (a) Energy consumed by five bulbs units Energy consumed by 1 heater Energy consumed by electric iron Total energy consumed by them =( 2 + 3 + 5) = 10 units         (b)1unit or kWh = 3.6 x 106J 10 units = 3.6 x 106 x 10 J    = 3.6 x 107J