Recent content by Raz91

Hello , I tried to solve this coupled ODE but with no success Does anyone know if there is an analytical solution to this equation? my problem is with the first & the second equations the term g*f is the my biggest problem i think once i have the solution for g - the solution for h is...

the electron moves λu while the light moves λ≈λu /β so the difference is λu [1/β-1] so how can I use this fact to find the wave length? I tried use the approximation β≈1-1q/(2*γ^2) for ultra-relativistic electrons but still didnt get the right answer...thank you

Homework Statement Homework Equations 2. (b) I didn't understand how can I find the app. wavelength The Attempt at a Solution I tried : the electron move over λu with velocity β so the wavelength is λ≈λu /β but its not the right answer. my lecturer told me I should...

so let's say I take a glass of water and put it in a closed box ( vacccum)- there will be no vapours?

so I have another question - what makes the water act like a gas ? I know that the evaporation temp. at room pressure is ~ 100 C , so if the temperture is < 100 and the pressure is ~ 1 atm why the water are gas? thank you

Hello , I was always wondering about this phenomenon : when i take out a cold bottle from the refrigerator , after a few seconds (lets say at room temperature) the bottle is surrounded by water. the question is - why is it? where did the water come from ? is it should happen with...

Homework Statement I uploaded a picture with the question Homework Equations my problem is : How should I find all the symmetries of the action ? Is there an easy way to recognize those symmetries or should I try all the symmetries I know and see if the action doesn't change...

As u can see , my result is depended on r (vector) for an arbitrary coherent state |alpha>...

but according to the defination of the electric field , any coherent state will lead to such an expectation value because it's an eigen-state of the annihilation operator.

I still don't understand where is it given ? it's just a "new name" for <Ex> , isn't it? of course the expectation value won't be an operator... so I don't see what's so special here or what should I do ... or f(r) is a known function in Electrodynamics that i should know ? Thank u ...

\HugeHomework Statement Consider a state of the EM field which satisfies \left\langle \textbf{E}_x(\vec{r})\right\rangle =f(\vec{r}) Find a coherent state which satises these expectation values.Homework Equations \textbf{E}(\textbf{r})=\frac{i}{\sqrt{2 V}}\sum _{\textbf{k},\lambda }...

Homework Statement Find the density of states g(ε) for an ideal quantum gas of spinless particles in dimension d with dispersion relation  ε= α|p|s , where ε is the energy and p is the momentum of a particle. The gas is confined to a large box of side L (so V = Ld) with periodic boundary...

Prove that the following two statements of the second law are equivalent (each one can be derived from the other): (a) “It is impossible for heat to flow spontaneously from a colder to a warmer body without causing other changes” (b) “It is impossible to convert all the heat taken from a...

I don't understand something - there are lots of functions that can be perpendicular to psi e.g (euclidean space)- the vector z (cartesian coordinates) , x is prep to z and y is prep to z but also the superposition (x+y) is prep to z. so by writing psi prep do u mean to the superposition...

this yields zero .. i didn't understand how it can help me thank you