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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.
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Solution
(i) I = 1 A
R = 300 Î
t = 1 h
Electrical energy consumed = `I^2xxRxxt`
= (1)2 (300) (1)
= 300 Wh
(ii) I = 2 A
R = 100 Î
Electrical energy consumed = `I^2xxRxxt=(2)^2(100)(1)=400Wh`
Thus, more electrical energy is consumed in case (ii).
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