Thermocouple is an arrange ment of two different metal to :-
convert heat energy into electrical energy
produce more heat
convert heat energy into chemical energy
convert electrical energy into heat energy
A kettle with $2\, littre$ water at $27\,^oC$ is heated by operating coil heater of power $1\, kW$. The heat is lost to the atmosphere at constant rate $160\, J/sec$, when its lid is open. In how much time will water heated to $77\,^oC$. (specific heat of water $= 4.2\, kJ/kg$) with the lid open ?
A tap supplies water at $10\,^oC$ and another tap at $100\,^oC$. .......... $kg$ hot water must be taken so that we get $20\, kg$ water at $35\,^oC$ ?
$10\,gm$ of ice at $0\,^oC$ is mixed with $'m'\,gm$ of water at $50\,^oC$ . ........ $gm$ is minimum value of $m$ so that ice melts completely. ( $L_f = 80\,cal/gm$ and $S_W = 1\,cal/gm-\,^oC$ )
Steam at $100°C$ is passed into $1.1\, kg$ of water contained in a calorimeter of water equivalent $0.02 \,kg$ at $15°C$ till the temperature of the calorimeter and its contents rises to $80°C.$ The mass of the steam condensed in $kg$ is
Pure water super cooled to $-15^o C$ is contained in a thermally insulated flask. Small amount of ice is thrown into the flask. The fraction of water frozen into ice is :