Recent content by Addez123
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B What is causing destructive interference in double slit experiment?
To say that the beam "split up" yet demand that it results in a single beam. What exactly is happening is what Im asking. Is it actually two separate rays of light? Could an electron split in two? If not then shouldn't it always be able to be defined by a single wave function and not have to be...- Addez123
- Post #8
- Forum: Quantum Physics
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B What is causing destructive interference in double slit experiment?
A wave is described as a sinus shaped wave, the √ of the probability function. It's not described as two separate wave functions interacting with eachother. Hypothetically, what happens if after the slit I separate the two areas with a sheet of paper. Now these "two waves" are forever separated...- Addez123
- Post #6
- Forum: Quantum Physics
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B What is causing destructive interference in double slit experiment?
When you do the double slit experiment with photons or electrons you get a wave pattern. At certain points no electrons are detected. This is said to be caused by destructive interference. Destructive interference of what? If we shoot single electrons, one at a time, from where is this...- Addez123
- Thread
- Destructive interference Double slit Double slit experiment Experiment Interference Slit
- Replies: 32
- Forum: Quantum Physics
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Solving the Density of States: Understanding dn/dE
Ahh yes yes! You get 1/2 from derivating the sqrt(E)! Now it all makes sense. Unbelivably grateful, thanks alot :) :)- Addez123
- Post #7
- Forum: Calculus and Beyond Homework Help
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Solving the Density of States: Understanding dn/dE
The 1/8th is because we calculate all states as if it were in a cartesian coordinate system and since n cant be negative we only cover the first octant. Its the surface of a sphere in the 1st octant * dn as they explain it.- Addez123
- Post #5
- Forum: Calculus and Beyond Homework Help
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Solving the Density of States: Understanding dn/dE
I literally can not explain how thankful I am for this response. I dont know how I couldnt read dn/dE as ##\frac{d}{dE}(n)## but it just never clicked. One final problem though. Their result has ##\sqrt{2}## in the denominator. I've done it twice but I get it in the numurator, isnt that correct?- Addez123
- Post #4
- Forum: Calculus and Beyond Homework Help
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Solving the Density of States: Understanding dn/dE
$$n = \sqrt{n_x^2 + n_y^2 +n_z^2}$$ $$E = \frac{n^2 \pi^2 \hbar^2}{2mL^2}$$ $$n = \sqrt{ \frac{2mL^2E}{\pi^2 \hbar^2} }$$ This is all given by the textbook. It's even as friendly as to say $$\text{differential number of states in dE} = \frac{1}{8}4 \pi n^2 dn$$ $$D(E) = \frac{...- Addez123
- Thread
- Density Density of states States
- Replies: 7
- Forum: Calculus and Beyond Homework Help
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Confused about quantum tunneling through 200V not eV
If charge q = e, moves through 200V, the energy given the electron is: $$\Delta U = qV = 200 V * e = 3.2 \cdot 10^{-17} J$$ I have no clue how to convert that into eV. I havnt done this kind of physics since middleschool, there was no introduction to any of this and next week we have to do...- Addez123
- Post #3
- Forum: Introductory Physics Homework Help
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Confused about quantum tunneling through 200V not eV
I have the equations to calculate transmission probability, my problem is that the barrier is given in Volts not electron volts. $$200V = e \cdot 200 eV = 3.2 \cdot 10^{-17} eV$$ I am not even sure if that's a correct conversion. But if it is then this "barrier" is extremly small and 99.999%...- Addez123
- Thread
- Confused Ev Quantum Quantum tunneling Tunneling
- Replies: 9
- Forum: Introductory Physics Homework Help
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Determine the particles most probable position
Good tip! I solved the ##\Psi^* \Psi## and got correct value though. Solved it again with your solution and it gave correct result too!- Addez123
- Post #10
- Forum: Advanced Physics Homework Help
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Determine the particles most probable position
Great! But I still get the wrong answer. $$4a^3 \int_0^{inf} x^3 \cdot e^{-2ax} = 4a^3 \cdot \frac {3}{8a^4} = \frac {3}{2a}$$ not 1/a as the answer suggests.- Addez123
- Post #7
- Forum: Advanced Physics Homework Help
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Determine the particles most probable position
That is true! So since it has no imaginary part the conjugate is simply itself? No changes?- Addez123
- Post #5
- Forum: Advanced Physics Homework Help
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Determine the particles most probable position
Isn't the conjugate simply reversing the minus sign on the exponential? Conjugate of ##xe^{-iax}## is ##xe^{iax}## according to wolfram alpha too.- Addez123
- Post #3
- Forum: Advanced Physics Homework Help
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Determine the particles most probable position
To get expected value I use $$E = \int \Psi^* Q \Psi dx$$ where Q = x $$4a^3 \int xe^{ax} \cdot x \cdot xe^{-ax} dx = 4a^3 \int_0^{\inf} x^3 dx$$ which is undefined. But the answer is suppose to be 1/a.- Addez123
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- Particles Position
- Replies: 10
- Forum: Advanced Physics Homework Help
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LaTeX Copying a symbol from latexhelp is extremly annoying
1. Go to: https://www.physicsforums.com/help/latexhelp/ WITHOUT being logged in. 2. Find a symbol you wish to use, such as \Psi 3. Then copy it and paste it into your equation 4. Voila! You ruined your entire document with this monstrocity- Addez123
- Thread
- Replies: 8
- Forum: MATLAB, Maple, Mathematica, LaTeX