Water of volume $2\, litre$ in a container is heated with a coil of $1\, kW$ at $27 \,^oC$. The lid of the container is open and energy dissipates at rate of $160\, J/s$. In how much time temperature will rise from $27\,^oC$ to $77\,^oC$ $[$ Given specific heat of water is $4.2\, kJ/kg$ $]$
A$8 \,\min\,\, 20 \,s$
B$6\,\min \,2 \,s$
C$7\, \min$
D$14 \,\min$
IIT 2005, Medium
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A$8 \,\min\,\, 20 \,s$
a Heat gained by water $=$ Heat supplied by container $-$ heat lost
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