A rigid tank contains 3 kg of subcooled liquid H2O at 50°C. An electric element in...

A rigid tank contains 3 kg of subcooled liquid H2O at 50°C. An electric element in the tank is turned on until the temperature rises to 95°C, where the H2O is now a saturated liquid on the verge of vaporizing. The tank is not well insulated, thus 10 kJ of heat are lost through its walls. Which is the correct energy balance for this process? Using the appropriate energy balance, determine the amount of electrical work, We, done during this process. If the process takes 5 minutes, what is the power rating of the electrical element in units of kW?

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Expert Solution

Facts and data we must know that

C_v of water = specific heat capacity of water at constant volume = 4.16 KJ / kg °C
although work done on the system is negative but while calculating the power of electrical element only its magnitude is considered. |- Work done| = Work done

genius_generous answered 1 year ago

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