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    Analysis of 2 body decay kinematics

    Thanks for the link. Equation 37.16 is the one that I was having trouble with, and apologies for my ignorance but I still don't see how they arrived at that formula? If p= E-m, then how do they arrive at that equation? I'm guessing the square root has something to do with getting the magnitude...
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    Analysis of 2 body decay kinematics

    Hi, I am learning about analysing particles decaying and am on this Wikipedia article: http://en.wikipedia.org/wiki/Particle_decay Under the 'Two body decay' subsection, there is a description of the momentum of particles 1 and 2 from the rest frame of the parent particle. I have two...
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    Understanding Particle Decay and Momentum Conservation in Relativity

    I am answering a question about a particle decaying into two other particles and one needs to find the momentum of the children particles from the rest frame of the parent. I found a very helpful article on Wikipedia under 'Particle Decay', however I am really confused by their mathematical...
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    Why Is the Electric Field Inside a Conductor Zero?

    I seem to be having trouble grasping a very basic principle in electromagnetism. I have been told, in numerous places, that the electric field inside a conductor is zero. (Electrostatics). Yet I keep coming across problems in the textbook like this one: "Use Gauss's Law to find the electric...
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    Calculating energy of electric field

    Homework Statement (a) Consider two concentric spherical shells, of radii a and b. Suppose the inner shell carries a charge q and the outer shell carries -q (both of them uniformly distributed over the surface). Calculate the energy of the electric field in this configuration...
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    Calculating average every from partition function

    1. I can't seem to get the same answer my textbook does, basically I need to calculate E (average energy) from the Partition function (Z) which is defined as: E=(-1/Z)*(dZ/dBeta) Where Z=(1/1-exp(-Beta*h*f)) (where h and f are constants and beta=1/kT for simplicity) So for my...
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    Absorbed dose of nuclear radioactivity

    You are great at explaining without doing to much of it yourself, thankyou have you been very helpful!
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    Calculating 238U/235U Ratio for Earth's Age

    So I ened up with 199.54/60.46 for the ratio of them in the past. So do I just put the number of u238 present (99.274) over 60.46? It seems a pretty pointless calculation..
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    Absorbed dose of nuclear radioactivity

    I have forgotten how to work out the number of moles, is it right to go n=M/MM so that M=1kg and MM=0.0117? in that case I got the number of nucleii to be 5.147e25, and then multiplied that by my previous answer for energy, and got a wopping 5.245e19 J.
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    Calculating 238U/235U Ratio for Earth's Age

    Ok well to work out the multipliers, I am not sure I have done it right, for 238U I divided 4.5e9 by 4.468e9 to see how many times it goes into it, then i multiplied that by two? because were going backwards from halfing them... and i did the same for 235U, is this the right method? I ended up...
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    Absorbed dose of nuclear radioactivity

    Homework Statement One kg of human body contains about 0.2% potassium of which 0.0117% is potassium- 40 (40K). 40K is radio active and in 89% of the time the product of the decay is a gamma ray of energy 1.46 MeV. If we assume that all of these gamma rays deposit their energy in the body...
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    Calculating 238U/235U Ratio for Earth's Age

    Homework Statement The Age of the Earth is 4.5 × 109 y. Use the information given in the following table to calculate the ratio of the number of 238U nuclei at the present time to the number of 235U nuclei at the time of the formation of the Earth. Isotope Half-life...
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    How do diffraction patterns change with laser and filtered light?

    The full question says "make a sketch graph oh the intensity vs position on the screen." so I am just using those graphs where there are a series of curves / maxima and minima on the x axis.
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    How do diffraction patterns change with laser and filtered light?

    1. The problem A HeNe laser (wavelength = 633nm) is used to illuminate an opaque plate containing a a specified aperture. The light which passes through the aperture falls on a screen at a distance of 4 m from the aperture plate. c) The aperture is replaced by two long rectangular slits...
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