An electric kettle draws 4, A current at 220, | vedclass

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(C) Power $P = V 	imes I = 220\, V 	imes 4\, A = 880\, W = 880\, J/s$.Heat required to raise the temperature of $1\, kg$ $(1000\, g)$ of water from

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$6.3$

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(C) Power $P = V 	imes I = 220\, V 	imes 4\, A = 880\, W = 880\, J/s$.Heat required to raise the temperature of $1\, kg$ $(1000\, g)$ of water from $20\, ^oC$ to $100\, ^oC$:$Q = mc\Delta T$$Q = 1000\, g 	imes 4.2\, J/g\, ^oC 	imes (100\, ^oC - 20\, ^oC)$$Q = 1000 	imes 4.2 	imes 80 = 336,000\, J$.Time taken $t = \frac{Q}{P} = \frac{336,000\, J}{880\, J/s} \approx 381.8\, s$.Converting to minutes: $t = \frac{381.8}{60} \approx 6.36\, min \approx 6.3\, min$.

An electric kettle draws $4\, A$ current at $220\, V.$ How much time (in minutes) will it take to boil $1\, kg$ of water starting from a temperature of $20\, ^oC$? (Assume the boiling point of water is $100\, ^oC$ and specific heat capacity of water is $4.2\, J/g\, ^oC$)

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