Recent content by Andrew Davies

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    Gibbs Free Energy of Van Der Waals Gas

    http://books.google.com/books?id=fSWEeTH1EeMC&pg=PA187&dq=calculate+Gibbs+free+energy+for+a+van+der+waals+gas&lr=&ei=Dv6NS-rZBYeuNYPX2dYM&client=firefox-a&cd=1#v=onepage&q=calculate%20Gibbs%20free%20energy%20for%20a%20van%20der%20waals%20gas&f=false Page 187 has a more elegant method.
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    High School Why is it tiring to push hard against a solid wall even though no work is done?

    Yes and No. Anytime there is movement of any kind within your body work is being done. Heart pumping, blood moving, muscles contracting, cells contracting, etc. However Feeling tired is not always the result of physical exertion. For instance if your brain was depleted in some chemical, say you...
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    Dereive an expression for an isobaric/isothermal change in entropy

    http://theory.phy.umist.ac.uk/~judith/stat_therm/node51.html
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    High School Why is it tiring to push hard against a solid wall even though no work is done?

    You are doing work. Your probability wondering how you can do work if your arm and the wall have no displacement. The answer is your muscles fibers are contracting and expanding. The work your doing is spread out throughout your muscle tissue. For example picture a bicycle that is stuck to a...
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    Graduate The fundamental thermodynamic relation

    Why is it that the The fundamental thermodynamic relation dU = Tds - PdV works in general even though Tds > dQ for irreversible processes. Likiewise PdV >/= dW for irreversible processes. Do the two irreversible effects cancel out. How does this happen physically.