Recent content by ThomasO

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    Why are zeros after a decimal point significant?

    I would write 8.0 with a dot over 0, in the same way we represent 1/3=0.3333... as 0.3 with a dot over 3. But I am not sure anyone would understand it.
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    Future Engineer: Advice on Choices at UoAuckland

    Among the engineers I know, those who perform the best on quantitative finances are electrical engineers, but the sample size is small. Search for "quantitative analyst" (in the case you didn't know this expression already). This may be the career your are looking for.
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    Thermodynamics,subcooled liquid

    Try considering that the heat added is equal to the increment on internal energy of the water. Which are the initial conditions, the final temperature and the amount of heat per unit mass or unit quantity of matter?
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    Confused how to use calculus in physics

    Jd0g33, ∫ means a "sum" over differential amounts. In ∫dE cosθ the differential amount is dE cosθ dE is a vector and dE x cosθ is its projection on the x-axis. Adding up all the projections of every dE, you get E_{x}. When taking ∫y(x)dx, the differential amount being added up is...
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    How to calculate the force between magnets?

    What about intregrating the differential forces between differential areas on each magnet? Would it work? Do you know what I mean?
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    Internal energy when filling an evacuated tank

    256bits, Thank you very much for your time! Your hints on "considering a control volume around the evacuated tank and considering the gas in the pipe as a system" and "if you consider that a force on a mass can move the mass a distance x at constant velocity if there is an opposing force of...
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    Internal energy when filling an evacuated tank

    I agree with you: "once some gas has entered the tank, any more gas entering into the tank has to do some work to compress that gas already in the tank." and this leads me to rephrase the objection (a) written above: a) the gas filling the evacuated tank has to do some work to compress that...
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    Internal energy when filling an evacuated tank

    Since the tank is an evacuated one, the gas entering the tank is submited to a free expansion, and during free expansion, no work is done by the gas, is it?
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    Internal energy when filling an evacuated tank

    This is the example 2.12 from "Introduction to Chemical Engineering Thermodynamics", 6th. ed, by Smith, Van Ness & Abbott: "An evacuated tank is filled with gas from a constant-pressure line. What is the relation between the enthalpy of the gas in the entrance line and the internal energy of...
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