Recent content by williamcarter

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    Cp & Cv Values: Example Problem 11.1 Explained

    Thank you , but how did you get these numbers from? They are not given in the statement of the problem. What about cv?
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    Cp & Cv Values: Example Problem 11.1 Explained

    Hello, I tried attempting the following example problem 11.1(please see below), however I don't quite get from where they got cp=1.00 and cv=0.717? I know that Q=m*cp*delta T=> cp=Q/(m*delta T) Q=n*cv*delta T=>cv=Q/(n*deltaT) Problem statement Their solution: How did they...
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    Engineering Bachelor of Engineering -- Importance of Grades

    Hi, I am a 3rd year on my B.Eng Chemical Engineering in the UK. I would like to know if possible, if big employer companies,worldwide, look just at the final degree mark, or at all marks from the transcript? What about for smaller companies? Thank you, William
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    Rankine Cycle Efficiency Calculation - Superheated Steam at 40 bar and 500°C

    Hi, Both work well, choose and use the one you are more comfortable with, and don't forget to pay attention in state 3 (you might have superheated or saturated)William
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    Reynolds Transport Theorem Derivation Sign Enquiry

    Alright, but why? In both cases the outwardly directed unit vector with the velocity vector are parallel. What makes it positive or negative?
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    Rankine Cycle Efficiency Calculation - Superheated Steam at 40 bar and 500°C

    Let 1= point after turbines when enters condenser Data for1: Pressure P1=3 KPa(KiloPascal) h1(entalphy1)=100.98 Kj/Kg v1(specific volume)=0.001003 m3/kg So we can use that Wpump(work that goes IN the pump)=v1(P2-P1)=h2-h1 (I)...
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    Rankine Cycle Efficiency Calculation - Superheated Steam at 40 bar and 500°C

    Yeah I did it again and got correct 0.400 or 40% efficiency, My mistake was on 3rd point on superheated I looked by mistake upwards a bit on other bit of table.Everything seems fine
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    Reynolds Transport Theorem Derivation Sign Enquiry

    Thank you, how come it ends up as positive(control surface1) in figure/picture 2? Because initially control surface 1 was negative but in picture 2 in final form of Reynold Transport Theorem ends up as +ve
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    Rankine Cycle Efficiency Calculation - Superheated Steam at 40 bar and 500°C

    Hi, *edit* I've got efficiency=0.40 or 40% so what u did is fine but I've used those tables: https://www.physicsforums.com/attachments/thermodynamic_tables_si-pdf.88587/
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    Reynolds Transport Theorem Derivation Sign Enquiry

    Alright, thank you but why in control surface 1 is -ve and in control surface 3 is + ve? How can we sense that? How to know when is in same direction as the system velocity and when is opposite? Thanks
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    Reynolds Transport Theorem Derivation Sign Enquiry

    Hi, Our lecturer explained us the Reynold Transport theorem, its derivation , but I don't get where the - sign in control surface 1 comes from? He said that the Area goes in opposite direction compared with this system. I can't visualise this on our picture. Can you please help me understand...
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    Sound propagation with altitude/height

    Thank you.
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    Sound propagation with altitude/height

    What about this?
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    Sound propagation with altitude/height

    If it is higher is has a greater distance from the source, therefore the sound/noise is less. But is it such a big difference given that there is 4m between the 2 floors? When I said there will be less noise on 2nd floor , SophieCentaur laughed at me on post #8
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    Sound propagation with altitude/height

    So the sound comes from outside the building, and it will get atenuated until it reaches 2nd floor right, I mean the people inside the building on the 2nd floor will hear less noise than those on the 1st floor right?But how exactly, and why? There are 4 meters between the 2 floors. I can think...