# All Questions

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### How Burmester's theory converts rotary motion of the crank to linear movement?

I have been studying the mechanism of Klann's Mechanical spider and there it was written that by Burmester's theory it converts rotary motion of the crank to linear movement. I tried searching but how ...
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### Do rainbows have ultraviolet bands and infrared bands?

We have seen that rainbows looks so colorful as we are only able to see the visible light only. Do they also have ultraviolet bands and infra-red bands, that we are unable to see? I know someone has ...
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### Exact diagonalization to resolve ground state degeneracies

I am studying a perturbed Toric Code model that is not analytically solvable. On a torus the ground state degeneracy of the unperturbed model is 4. Once we turn on the perturbation there is a change ...
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### Magnetic field due to long current carrying conductor at a point near its end [duplicate]

How can one show that the magnetic field due to an infinite long current carrying conductor (length a) at a point near its end is given by $$B = \frac{\mu_0I}{4\pi a}$$ using Ampere's Circuital ...
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### Determine travel for different rate springs in series

I've found a lot of information about calculating combined spring RATE, but none of the examples talk about the force experienced by each individual spring when multiple springs are "stacked" in ...
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### Any good reference on crystal optics?

I am primarily interested in the birefringence phenomenon. Any good reference? I want something above the general physics level.
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### In general terms, what key elements are necessary for resonance to exist in a physical system?

I found a related question An Analogy for Resonance, and John Rennie gives a good explanation using description of the harmonic oscillator. But I'm really looking for an accurate and complete list of ...
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### Adjoints in occupation number representation

I am having some trouble understanding how to compute things in occupation number representation. I believe my problem is only implicitly dealt with in the notes I have read. A simple example should ...
186 views

### Where do sound waves go after being heard?

I honestly can't come up with anything that makes sense, because obviously, energy cannot be created nor destroyed. I think the question is pretty self-explanatory, so there isn't much to say here.
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### Can isotropic states have bound entanglement?

Let us consider the maximally entangled state $$|\psi\rangle=\frac{1}{\sqrt{n}}(|0,0\rangle+\cdots+|n-1,n-1\rangle)$$ and construct the pseudo-pure state ...
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### Magnetic field outside an infinite solenoid

Can someone explain to me how the magnetic field cancels outside a solenoid of infinite length mathematically (using an integration or something)?
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### Peskin's book page 334 proof of $Z_1=Z_2$ to all orders in QED perturbation theory

Peskin in his QFT page 334 argued that $Z_1=Z_2$ to all orders in QED perturbation theory, but I couldn't understand his argument: ... With a generalization of the argument given there (section ...
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### Understanding electric field and potential inside an half-connected wire

Let's say we have a 9 V battery and a wire as shown in the image below: Let's assume H is the reference for measuring potential. I know the potential in F is 9 V, and I know the electric field in F ...
528 views

### Can Lagrangian mechanics be justified without referring to Newtonian mechanics?

Are there any ways of justifying Lagrangian mechanics as a foundation of classical physics, without referring to Newtonian mechanics? In other words, what is the deeper reason or intuition why ...
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### Has the effect of magnetic fields on time ever been examined experimentally?

Relativity of time can be examined with satellites as gravitational or acceleration. Is there any similar experiment with intense magnetic fields?
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### entropy of a closed system undergoing an irreversible process should increase,decrease or remain same?

The answer in my book says it will increase. According to me it will increase if heat is added to the system But if heat is being removed it may increase decrease or remain the same depending upon ...
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### $L^p$-weighted enstrophy calculations

Mathematician here, only somewhat familiar with physics, but finding myself involved in a research project on fluid dynamics. I'm studying a 3D simulation of turbulent fluid flow, and we are currently ...
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### entropy change during irreversible heat loss [duplicate]

When a thermodynamic system gains heat if the heat gain is irreversible then there is a entropy generation along with the entropy transfer..so is there a similar entropy generation associated with ...
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### What force does a magnetic field of a certain strength apply to an object?

Disclaimer: This question is mostly to fact-check an "Elementary" episode and is not home work related at all. For the curious, in that episode, a "20 tesla magnet" is used to propel bullets inside an ...
### Why is the limit to observe quantum phenomena $k_B T < \hbar \omega_0$ in cavity QED?
In cavity QED you have to cool down the appartus so that quantum effects may be observed in a way that $k_B T << \hbar \omega_0$. I suppose that $\omega_0$ here means the frequency which the ...