Recent content by XCBRA

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    Relativistic decay of a particle

    Ahh yes, however that was only a mistake I made when typing the problem up to pf, my calculations had both with the -ve sign to get the result below it.
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    Where to learn about Density of States?

    Thank you for the help,I will be looking at those books and I will be enrolling in one of those classing in the fall, I was hoping to rea dup ont he subject before I went back to university Thank you for the help.
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    Relativistic decay of a particle

    Homework Statement Pions can decay via the reaction π+ → μ+ νμ. Show that the energy of the neu- trino in the rest frame of the pion is given by E_v = \frac{m^2_∏-m^2_μ}{2m_∏} Pions with energy Eπ in the laboratory frame (Eπ >> mπc2) decay via the above reaction. Show that the...
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    Where to learn about Density of States?

    I am the point where i need to learn about Density of states, how to explain the concept and how to then calculate it for different systems, however I am unable to find any texts that really explain it on an introductory level. If anyone knows any sources or text that have a good introductory...
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    Collimating light from Optical fibre problem

    Homework Statement A thin lens of focal length f is used to collimate the light emerging from two different optical fibres. When used with a first fibre of small core diameter and numerical aperture NA it acheives a diffraction limited divergence of θ1 for the collumated beam. Find the...
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    Thermodynamics of a rubber band

    Homework Statement For a stretched rubber band, it is observed experimentally that the tension f is proportional tot he temperature T if the length L is held constant. Prove that: (a) the internal Energy U is a function of temperature; (b) adiabatic stretching of the band results in an...
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    Problem solving Heat Diffusion Equation

    Ahh that makes better sense. Thanks for the help, I was able to solve to give: Tcos(wt-x\sqrt{\frac{w}{2D}}) e^{-x\sqrt{\frac{w}{2D}}}
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    Problem solving Heat Diffusion Equation

    Homework Statement One face of a thick uniform layer is subject to a sinusoidal temperature variation of angular frequency ω. SHow that the damped sinusoidal temperature oscillation propagate into eh layer and give an expression for the decay length of the oscillation amplitude. A cellar...
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    Shwoing the sensitivity of many body systems oi small perturbations

    Homework Statement Imagine we are observing the motion of frictionless, elastically colliding billiard balls. Using sensible assumptions about the size of things, show that, if someone enters the room, small deflections of the balls due this visitor's gravitational pull will completely...
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    Magneostatics - hollow sphere of spontaneous magnetization

    Homework Statement a) A hollow magnetic sphere of internal radius a and external radius b, has a uniform spontaneous magnetization M per unit volume. SHow that the field strength in the internal cavity (r<a) is zero, and that the external field strength (r>b) is the same as that of a dipole...
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    Solving for magnetic field from a solonoid

    For this problem yo are trying to calculate the field between the coils. The formula you are using for a solenoid is therefore not valid as it is only valid in the cenetre of a long solenoid. Try treating each coil as a loop of wire of N turns.
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    Understanding Dipole Behavior in a Dielectric Medium

    Ahh ok that makes a lot more sense, thank you for the help.
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    Understanding Dipole Behavior in a Dielectric Medium

    Homework Statement A dipole p is situated at thecentre of a spherical cavity of radius a in an infiite medium of relative permitivity \epsilon_r . show that the potential in the dielectric medium is the same as would be produced by a dipole p' immersed in a continuous dielectric, where...
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    Electric Field in a cavity of a dielectric medium

    The question I had asked earlier was indeed the first part of the question, but I am now having trouble with he second part and felt necesary to include the first part answer and soltuion to give the context to the second part. I just realsied that there is typo in and it should indeed...
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    Electric Field in a cavity of a dielectric medium

    Homework Statement The polarization charge in the surface of a spherical cavity is -\sigma_e \cos\theta ,at a point whose radius from the centre makes and angle \theta with a give axis Oz. Prove that the field strength at the centre is \frac{ \sigma_e}{3 \sigma_e} parallel to Oz. If the...
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