All Questions

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Fresnel Zones-How are they Formed?

How are Fresnel Zones formed? What phenomena of light allow ellipsoid areas to be in phase? I've tried reading articles, but they more or less introduce me to characteristics of light, and then tell ...
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Point of Lagrange multipliers

I am trying to understand how for a constrained system the introduction of Lagrange multipliers facilitates the incorporation of the holonomic constraints. I am using Classical Mechanics by John ...
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Statistical mechanics prerequisite [duplicate]

Ill be taking senior level and graduate course in statistical mechanics in a month. I was wondering what would be the best statistics and probability textbook to prepare for it? Im currently ...
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What is power required to pump out the water with constant speed? [on hold]

Let density of water = D unit cross section of pipe = A units velocity at which water is to be drawn = V units Statement 1: Here DAV = mass ejected per unit time so (DAV)V ...
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Oscillation Question [on hold]

Now normally (if it was a block not rotating) all you would have to do is use $w^2 = k/m$ and $E= \frac12k(A\cos(2wt+\theta))^2 + \frac12m(Aw\sin(wt+\theta))^2$ or in other words the translational ...
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Why does a cyclic coordinate reduce the dimension of the cotangent manifold by 2?

Our professor's notes say that "In general, in Hamiltonian dynamics a constant of motion will reduce the dimension of the phase space by two dimensions, not just one as it does in Lagrangian ...
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Is There Any Work Done By Normal Reaction Force even if point of application of force is not getting displaced?

Suppose that I am standing on the ground and I suddenly jump and rise up to any certain height.So accordingly I would have gained some speed i.e. Kinetic Energy during the process of jumping.According ...
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Likelyhood of the creation of a single unbound quark in the collision of very high energy particle beams

I am going over old exam and am not understanding the logic behind the answer given in the mark-scheme. A beam of protons and antiprotons attain energies of 1400 GeV in a synchrotron. Why is it that, ...
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How to find time, acceleration under this situation

I am trying to solve the following. An object of mass $m$ slides on a horizontal surface with initial velocity $v_0$. If the kinetic friction between the object and mass is given by $\mu$, find ...
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How to calculate the Partition function of a large sparse Hamiltonian(band matrix)?

As in most tight-binding atomic model, the Hamiltonian $H$ is sparse and in my problem, it is a band matrix. How to compute the partition function $Z = Tr\left( {{e^{ - \beta \hat H}}} \right)$ ...
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Electron energy from muon decay

When a muon decays from rest, typically what fraction of the energy is carried off by the electron? I tried looking into some papers, but I wasn't sure how to interpret the graphs they displayed.
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Formation of magnetic field in an inductor

I can't really imagine the way the magnetic field would be created due to electron flow in an inductor. We say that in a straight current carrying conductor the magnetic field follows the thumb rule. ...
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Fluid Flow Question [on hold]

A good explanation as to why two filters with differing geometry change the value of a flow rate when the measure pressure before the changed geometry is held relatively constant. What is the simplest ...
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Vapor pressure formula

Can anyone please help me work out the formula for getting the vapor pressure given: air temp, air temp wet and air pressure (wet baro)? These where entered into a DOS program and know one remembers ...
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Is forward scattering = no scattering?

What is forward scattering? If it is equivalent to no scattering, then why not call it "no scattering"?
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Relation between voltage and current [duplicate]

What I know is that voltage is the electrical pressure which is required to drive the electrons in a circuit. According to that we have higher currents when there is a high voltage. Ohm's law confirms ...
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Oscillatory Motion — Period of Two Rollers [on hold]

. Center of mass implies something with moments. Force of friction is related to the normal force, which is caused by both rollers, and the normal force on each roller would depend on the center of ...
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References: QFT Chaos

Recently I've read about put chaos into QCD. By now, I'm a bit confused and at the same time thinking that it's a good idea. I'm looking for references on this but I'm only finding a very small ...
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What do they mean by $\langle u_i |O| u_j\rangle$ in quantum mechanics

UCSD's online QM notes, as usual, starts stating that QM operators are Hermitian and says that operator $O$ elements can be computed by $$O_{ij} = \langle u_j|O|u_i\rangle$$ The $u_i$ are ...
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How many minutes does a sundial change every day?

I'm planning to create a sundial in Ghana (10° 28.852', 0° 26.032') in July 2014. I will stay there for about 3 weeks. Do I need to adjust the numbers anywhere in these 3 weeks? I know the shadow's ...
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QFT Dyson series: why are we solving the Schrodinger equation?

In quantum field theory, the solution of the time evolution operator of the Schrodinger equation (in the interaction picture) is given by Dyson's series, which is used to calculate the S-matrix. Why ...
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Curvature approaching infinity

I assume that all mass-objects curve time-space but the curvature is only measurable with celestial bodies large enough to be significant gravity-wells. What you call "curvature" seems to me to be ...
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Does quasi-static motion imply zero energy dissipation?

When a droplet is deposited on a surface with some surface roughness and subsequently tilted it can stick due to pinning (think of droplets on a window after rain). What I am interested in is ...