Homework Statement
In the Rotor Ride at the NM State Fair, passengers stand with their
backs to the wall in a giant rotating drum with a radius of 10 feet. The drum
is brought up to a speed of 33 1/3 RPM, and then the floor is lowered, leaving
the passengers suspended above a giant hole in the...
Hey guys, I've been doing a lot of research looking for a fluid that has a high expansion ratio that does not leave the liquid state.
the idea is that the fluid could either:
- using heat will expand and contract using hot and cold cycles
- using electricity (not necessarily needing...
If a metallic ball is place under a giant hollow top, and the top starts to rotate. Along with the top, the metallic ball will also start to rotate. Thus my question is the ball motion is under inertial frame of reference or non-inertial ?
Homework Statement
It is known that there is a 36% probability of obtaining S_z = \hbar/2 and therefore a 64% chance of obtaining S_z = -\hbar/2 if a measurement of S_z is carried out on a spin 1/2 particle. In addition, it is known that the probability of finding the particle with S_x =...
There is an old controversy in quantum mechanics, with arguments on the borderline between science and philosophy, on the question whether the quantum state describes an objective reality associated with a single system, or mere probability describing properties of a large ensemble of equally...
Homework Statement
We have a horizontal cylinder with an ideal piston, both are made from a heat nonconductive material. There is 10 liters of steam at 3 bars and 200 degrees Celsius in the cylinder. The cylinder is surrounded with atmosfere with pressure of 1 bar and temperature at 20 degrees...
Equations of state for photon gas and relativistic electron gas
This entry develops equations of state that are useful in calculations about cosmology and about the insides of stars. The first calculation is for a photon gas and the second is for a 'relativistic' gas of particles with mass...
I am an undergrad and for the most part I am looking for a good physics class to take. I am considering taking solid state physics at the level of Kittel as its one of the only physics classes offered at the undergrad level this semester that I haven't taken. I haven't taken quantum mechanics...
Do you think we will ever be able to create a simplified computer simulation of the universe using the cosmic microwave background as the initial state that would generate the true locations of galaxies or at least galaxy clusters, and then be able to find our own galaxy or galaxy cluster within...
In Carroll's we read
...The Unruh effect teaches us the most important lesson of Quantum Field Theory (QFT) in curved spacetime, the idea that "vacuum" and "particles" are observer-dependent notions rather than fundamental concepts.
I wonder are we talking about the same observer or two...
Hi guys,I am new for programming. I made my first attempt to solve an heat equation by finite difference method and wrote a code for it in Matlab.I got a solution but i need help from you guys to (vectorize) increase the speed of my program.
((∂^2 T)/(∂x^2 )+(∂^2 T)/(∂y^2 )+(∂^2 T)/(∂z^2...
Hi friends i am trying to solve heat equation for a single time domain,with Finite Difference Method. I wrote a program in MATLAB,it sucessfully worked, but as i increse the number of points, my program is taking lots of time to give out result.
Can anybody help me in increasing the speed of my...
Hi all,
I am really curious about the final state conjecture in general relativity, but I don't really understand it... There seems to be a really good explanation provided by Willie Wong here:
http://math.stackexchange.com/questions/50521/open-problems-in-general-relativity
however it is...
Hi PF.
If I have two identical bosons, one in the single-particle state \phi_{a}(x) and the other in the single-particle state \phi_{b}(x), the two-particle state of the system would then be :
\psi(x_{1},x_{2}) = \frac{1}{\sqrt{2}}\big(\phi_{a}(x_{1})\phi_{b}(x_{2}) +...
Hi
Here is the number for the measured frequency for hydrogen 1s to 2s transition:
2 466 061 413 187 035 Hz
By way of interest, what is our most accurate theoretical calculation of this number? I've tried the ordinary Bohr formula and it is only accurate to about 4 places.
I'm also...
Hello, I have an FSM which has 1 serial input and 4 outputs. The FSM must react to the table attaced in file.
I can see that if the input is(for example)4 the output is 7(+3).
I have to draw a state diagram(mealy). I can't solve it. Need some help
Thanks
Hi Everyone,
I was curious as to what the most current model in solid state physics is. I've studied the Einstein and Debye Models in Stat Mech, as well as free electron and tight binding models in an intro solid state class, but these models are rather old(which does not imply they are...
Take a look at the attachment, my question is obvious from the colored points. The attachment is from:
"state-of-the-art formulas for helicity amplitude calculation and all that
(version 2.4)
PART Ia. Spherical-Vector Method for Helicity Amplitudes
(FORMALISM)
Ken-ichi Hikasa"
I think...
my question is about the no-communication theorem in quantum mechanics:
Assume that i have a pair of entangled photons which are entangled on their polarization. also assume that i send one to alice and another to bob. and alice wants to send a message to bob. no communication theorem states...
Since the electromagnetic and the weak force unify at high energies, why do physicist continue to count four fundamental forces? With that kind of thinking why not break symmetry with the electromagnetic force and say there are five fundamental forces?
When the B field gets too high it breaks the superconducting state. And then the B field can exist inside the conductor. When the field increases to point where it breaks the state is this because the cooper pairs flowing near the surface experience a force on their spin and then break them...
Homework Statement
I've been reading Leonard Susskind's Theoretical Minimum volume on QM, and enjoying it quite a bit - the book doesn't include exercise solutions at the end though, and if they exist online for this volume I haven't been able to find them. (Perhaps if such solutions...
Hi, I'm not from Software Engineering background and I'm trying to learn State Machine Diagrams on my own by looking at resources on the internet.
I'm trying to come up with a State Machine Diagram for a telephone but I can't seem to find an answer on the internet. Can you help me by telling...
I am trying to understand why I can specify the specific volume v of a fluid element as a function of the equilibrium pressure, p, and the equilibrium entropy, s. This is for example done in this article http://www.sno.phy.queensu.ca/sno/str/SNO-STR-95-051.pdf , on this website...
Hi, there. The following is copied from a book " atom-photon interaction " by Prof. Claude Cohen-Tannoudji, Page 415.
I do not understand it at all. I do know some thing about the coherent state.
such as
##a |\alpha\rangle = \alpha |\alpha\rangle##
and
##|\alpha\rangle =...
First of all..I want to be clear about steady state..what actually it means..?? Does it mean state of constant current flowing across..?
In my book..its written that in steady state current in inductor and voltage in capacitor is zero , hence energy consumed is zero fotr both in steady...
Hi.
I was reading time-dependent perturbation on Sakurai and it mentioned that a certain state was "populated". What does that mean? I don't think it mentions it in any previous chapter.
Thank you for your time.
Hi Everyone:
I think some of you who familiar with quantum-optics know that the local photonic density of state can be calculated by the imaginary part of electromagnetic Green's function.
The Green's function can be further presented by the dipole's mode pattern as
G =...
The usual "proof" entropy is a state property is like that:
"Consider a system which undergoes a reversible process from state 1 to state 2 along path A, and let cycle be completed along path B, which is also reversible. Since the cycle is reversible we can write:
∫1-2 δQ / T + ∫2-1 δQ / T...
In a past physics gre question (https://www.physicsforums.com/showthread.php?t=192334), we make use of the idea that the ground state energy of two ions that have spin is when the spins are aligned.
However, the ground state of the helium atom is a spin singlet state, which is a linear combo...
dear sir,
when hydrogen atom is converted to plasma state, the free electron must be released. i am curious to know where does this electron go in case of plasma in stars.
thank you.
"Hartle and Hawking suggest that if we could travel backward in time toward the beginning of the universe, we would note that quite near what might have otherwise been the beginning, time gives way to space such that at first there is only space and no time. " -Wikipedia
Does this mean that...
When entropy is complete doing what it is doing is their an idea as to what is left i assume all the protons have decayed. What would the very last particle be and what would it decay into?
Homework Statement
The titleHomework Equations
NahThe Attempt at a Solution
It has no free moving ions or electrons
Then, my teacher saw the electrons and gave 0 marks to the question(It was on the test paper)
He said that if he didn't see electrons there, he would have given a mark.
Why? I...
Homework Statement
0.02 kg of ice and 0.10 kg of water at 0 degrees Celsius are in a container. steam at 100 degrees Celsius is passed in until all the ice is just melted. How much water is now in the container?
Specific latent heat of steam = 2.3 * 10^6 J/kg
Specific latent heat of ice = 3.4...
Homework Statement
For a system of particles at room temperature (use kT = 0.026 eV), the energy of a single particle state is 0.01 eV greater than its chemical potential, so that ε-μ = 0.01 eV. Computer the average occupancy of this single particle state, as well as the probability of the...
Hello everybody!
I have a choice between an out of state university, which costs a lot, and a community college.
Either way I plan to transfer to the "best"(intellectually rigorous) school I can. (I want to be around primarily people who think so I am thinking a college like reed college...
Hello guys,
Homework Statement
the problem goes as follows:
"Which measurement should you do on a statistical ensemble of qubits in order to distinguish between the pure state |Ψ>= cos(θ)|0> + sin(θ)|1> and the mixed state ρ=cos^2(θ)|0><0| + sin^2(θ)|1><1| "
Homework Equations
I am not...
I am referring to an experiment mentioned in Quantum Entanglement lecture:
(Starting from: 14:20)
In that lecture, as far as I understand, the description of the experiment is as follows:
Assume:
"up state" means north pole is vertically upwards
1. Preparing the state: Prepare...
If I define a state ket in the traditional way, Say:
$$|\Psi \rangle =\sum _{ i }^{ }{ a_{ i }|\varphi _{ i }\rangle \quad } $$
Where $$a_i$$ is the probability amplitude.
How does:
$$\hat {H } |\Psi \rangle =E|\Psi \rangle $$ if the states of $$\Psi$$ could possibly represent states...
I have this equation
u0(x) = a0x2(1-x)2 for 0≤ x ≤ 1
= 0 for x>1
i have to investigate how will a solitary initial state such as the one above deform as time goes on.
I know it will not deform if c is constant. when they say I must do this by a well-lnown method and produce video...
Hello all!
I've been trying to go from the second to the third equation shown in the image.
Here, \vec{H}(\vec{r})=e^{i\vec{k}\cdot\vec{r}}\vec{u}_\vec{k}(\vec{r}) is the Bloch state for some periodic dielectric arrangement.
I have tried using the identity that...
The eigenstates of a hydrogen atom are stationary states with definite values of energy. Now, as I understand it, the quantum mechanical state of the electron in the hydrogen atom is really a linear superposition of all these energy eigenstates. So this should mean that there is a finite...
So, the igbt bridge system i have going is a 600 volt 300 amp full bridge of cm300 igbt's and i was wondering if a .660uf tank capacitor is too big for my system. The mmc is made out of 2000 volt 1uf capacitors, 2 strings of 3 in series. Thank you.
For part a I have (H0-ω\hbarm)|nlm>, which I think the (H0-ω\hbarm) part is the eigenvalue of the Hamiltonian, also is the energies?
And mainly, I am not sure how to approach part b, the time variable is not in any of the states. I saw this in our lecture notes: ψ(r,t)=∑Cnψn(r) e-iEnt/\hbar...
In the operation $$U(\Lambda)|{\bf p}\rangle=|{\Lambda\bf p}\rangle,$$ if we define the state covariantly, $$|{\bf p}\rangle=\sqrt{2E_{\bf p}}a_{\bf p}^\dagger|0\rangle,$$ then does the unitary operator U(\Lambda) affect the factor of \sqrt{2E_{\bf p}}? In other words, can we write...
If a system is made up by two subsystems, for example, the atom and the photon. and let's assume the state of the atoms is described by |\phi\rangle, while the state of the photons can be described by |n\rangle, The Kronecker product of the |\phi\rangle and |n\rangle can be used to describe the...
Hello readers,
Given the potential
V(x) = - 1/ sqrt(1+x^2)
I have found numerically 12 negative energy solutions
Now I want to try to solve for these using matrix mechanics
I know the matrix form of the harmonic oscillator operators X_ho, P_ho.
I believe I need to perform the...
Homework Statement
The Hamiltonian of helium can be expressed as the sum of two hydrogen Hamiltonians and that of the Coulomb interaction of two electrons.
\hat H = \hat H_1 + \hat H_2 + \hat H_{1,2}
The wave function for parahelium (spin = 0) is
\psi(1,2) = \psi_S(r_1, r_2)\dot...