Calorimetry with flow rate
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A coil is immersed in a calorimeter.
Is passed through the coil a current of water.
is the specific heat of water.
At the input, the water is at a temperature of , the output is the calorimeter temperature which, through an electric heater, is maintained at .
Calculate the power required from the heating resistance if the water flow rate through the coil is .
Is selected as the closed fluid system in the calorimeter and a mass to the input at the instant .
At time , the system consists of the fluid in the calorimeter and a mass at the output, at the calorimeter temperature.
The first law of thermodynamics then gives : (assuming steady state)
The resistance is ; calculate the current intensity .
Passing another liquid in the coil and for the same conditions (temperature and intensity), we must ensure a flow rate of .
Calculate the specific heat of the liquid.
We have the equality :