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

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(B) The power consumed by the electric kettle is $P = V 	imes I = 220\, V 	imes 4\, A = 880\, W$.To boil $1\, kg$ of water,the heat required is $H =

Vedclass · Accepted Answer

$6.3$

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(B) The power consumed by the electric kettle is $P = V 	imes I = 220\, V 	imes 4\, A = 880\, W$.To boil $1\, kg$ of water,the heat required is $H = m 	imes c 	imes \Delta T$.Given $m = 1\, kg$,$c = 4200\, J/kg\, ^\circ C$,and $\Delta T = (100 - 20)\, ^\circ C = 80\, ^\circ C$.$H = 1 	imes 4200 	imes 80 = 336000\, J$.Since $H = P 	imes t$,the time $t$ in seconds is $t = H / P = 336000 / 880 \approx 381.82\, s$.Converting to minutes: $t = 381.82 / 60 \approx 6.36\, minutes$.Rounding to the nearest provided option,the correct answer is $6.3\, minutes$.

An electric kettle takes $4\, A$ current at $220\, V$. How much time will it take to boil $1\, kg$ of water from room temperature $20\, ^\circ C$? The temperature of boiling water is $100\, ^\circ C$. (Assume specific heat of water $c = 4200\, J/kg\, ^\circ C$)

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