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In which of the following cases more electrical energy is consumed per hour?
  1. A current of $1$ ampere passed through a resistance of $300$ ohms.
  2. A current of $2$ amperes passed through a resistance of $100$ ohms.
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  1. $R = 300$ ohm, $I = 1A, t = 1h$
$P = I^2 R = 1^2 \times 300 = 300W$
$E = P \times t = 300 \times 1 = 300Wh$
  1. $R = 100 $ ohm, $I = 2A, t = 1h$
$P = I^2 R = 2^2 \times 100 = 400W$
$E = P \times t = 400 \times 1 = 400Wh$
Hence, in case (ii), the electrical energy consumed per hour is more.
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