Recent content by vthem

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    Limiting Behavior of xsin(1/x)

    I just edited it!
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    Nuclear decay of a mixture of P and S. (2009 USAPhO Question A2)

    Thanks a lot for the reply! (I also hit the Thanks button :P ) So because the λ of the long lived isotope is too little the slope will give me the other λ. Right?
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    Nuclear decay of a mixture of P and S. (2009 USAPhO Question A2)

    I got λ=-0.00856 and b=8,68. This is only for S though. Excel file
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    Limiting Behavior of xsin(1/x)

    In general, whene you have a clogged function (like \sin or \cos) times 0 the \lim will be 0. It is usefull to think like this! Taking the inequalities and sandwich theorem will allways help! I usually face these limits like this: |x \sin(\frac 1 x) | \leq |x| ⇔ -|x| \leq x \sin(\frac 1 x)...
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    Nuclear decay of a mixture of P and S. (2009 USAPhO Question A2)

    I'm asking which plot...
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    Limiting Behavior of xsin(1/x)

    Just take abs(xsin(1/x))=<abs (x).
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    Nuclear decay of a mixture of P and S. (2009 USAPhO Question A2)

    In a \ln{|\frac{dN}{dt}}| - t diagram and see where the slope is constant or you mean something else?
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    Nuclear decay of a mixture of P and S. (2009 USAPhO Question A2)

    |\frac{dN}{dt}|=λ\cdot N_{0,P}\cdot e^{-λt}⇔\ln{|\frac{dN}{dt}}|=\ln(λ\cdot N_{0,P})-λ\cdot t Then on a \ln{|\frac{dN}{dt}}| - t diagram the slope would be -λ and it would "cut" the \ln{|\frac{dN}{dt}}| axis on \ln(λ \cdot N_{0,P}). Since T_{1/2}=\frac{\ln2}{λ} I have both a and b. What...
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    Nuclear decay of a mixture of P and S. (2009 USAPhO Question A2)

    The answer is not provided by AAPT. Homework Statement A mixture of ^{32}P and ^{35}S (two beta emitters widely used in biochemical research) is placed next to a detector and allowed to decay, resulting in the data (attached) below. The detector has equal sensitivity to the beta particles...
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    How to use these books for physics olympiad?

    I use University Physics (by HD Young) for praparation. I would recommend that you solve the "Problems" and the "More Advanced Problems". You may skip the exercises. Then try solving more exercises from problem books like Irodov.
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    How to use these books for physics olympiad?

    I'm not sure if a student has to study that long. In fact I think that it is impossible! I have met students who have win medals in IPhO and IMO and allthough they study a lot of time they never do so that long. In fact I do know a student who got a bronze in IMO 2011 with a 2 month preparation...
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    Calorimetry & Thermodynamics textbook

    I am studying for the IPhO and I am using University Physics by HD Young. I think that the book's problems in Calorimetry and Thermodynamics are not very good and also there are not detailed solutions to the problems. Can anybody propose to me any good textbook with more problems and detailed...
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