Property Tables Question [Thermodynamics]

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AfterSunShine
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Homework Statement


Given
Pressure=P=700 KPa
Specific Entropy = s = 7.6953 KJ / ( K Kg )

Find the Specific Enthalpy (h)

Homework Equations


No equation
Am using the property tables at the end of the following book :
Thermodynamics, an engineering approach, by Yunus A. Cengel and Michaek A.Boles 7th edition.


The Attempt at a Solution


By obtaining the values of s_f and s_g from Table A.5 and compare it to s, the state is Superheated Vapor.
This means I will use Table A.6
The pressure = 700 KPa = 0.7 MPa
But the most closest pressure to this pressure is 0.6 MPa and 0.8 MPa
So I will use interpolation like that
P (MPa) h
0.6 h1
0.7 h
0.8 h2

h1 and h2 must be calculated in order to apply interpolation to find h
To find h1,h2 Need to know T of the state
But I do not how to find it

Help please.
 
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Look up double interpolation.
 
I did not get it :\
 
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AfterSunShine said:

Homework Statement


Given
Pressure=P=700 KPa
Specific Entropy = s = 7.6953 KJ / ( K Kg )

Find the Specific Enthalpy (h)

Homework Equations


No equation
Am using the property tables at the end of the following book :
Thermodynamics, an engineering approach, by Yunus A. Cengel and Michaek A.Boles 7th edition.



The Attempt at a Solution


By obtaining the values of s_f and s_g from Table A.5 and compare it to s, the state is Superheated Vapor.
This means I will use Table A.6
The pressure = 700 KPa = 0.7 MPa
But the most closest pressure to this pressure is 0.6 MPa and 0.8 MPa
So I will use interpolation like that
P (MPa) h
0.6 h1
0.7 h
0.8 h2

h1 and h2 must be calculated in order to apply interpolation to find h
To find h1,h2 Need to know T of the state
But I do not how to find it

Help please.

If p and s are known, the state is known totally, including sp. enthalpy h and temperature T. Just need to know how to use your (superheated) steam tables.