Question

In which of the following cases more electrical energy is consumed per hour?

(i) A current of 1 ampere passed through a resistance of 300 ohms.
(ii) A current of 2 amperes passed through a resistance of 100 ohms. 

 

Answer 1

(i) I = 1 A
    R = 300 Ώ
    t = 1 h
    Electrical energy consumed = `I^2xxRxxt`
                                                   = (1)² (300) (1)
                                                   = 300 Wh
(ii) I = 2 A
     R = 100 Ώ
    Electrical energy consumed =  `I^2xxRxxt=(2)^2(100)(1)=400Wh`

    Thus, more electrical energy is consumed in case (ii).