Recent content by Raynor49

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    What's the nature of a force acting on this gas? (Thermo)

    Homework Statement A gas in equilibrium has distribution function: f(p,r) = C0*(1+y*x)(2*pi*m*k*T)-3/2*exp(-p2/(2*m*k*T)) where x is the distance along an axis with fixed origin, and y is a constant. What's the nature of the force acting on this gas? Homework Equations Maxwell bolztmann...
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    Probability of Spin in Y-up direction

    Homework Statement a) If a spin-1/2 particle is in the up spin state along z, what is the probability that if its spin along the y-direction is measured it will be found to be pointing in the “up” direction along y? (b) Calculate the expectation values of the components of S, i.e. {Sx, Sy...
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    Square Hill Barrier, weird question wording

    Ok cool, I think I got it. Thanks so much for all your help! :)
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    Square Hill Barrier, weird question wording

    Awesome, ok. Sorry for the late reply, been having to deal with midterms. So k1=k3, can I also say that k2=i*k1 ? Since I thought k2=i*k1=i*k3 but when I sub that in it ends up cancelling out everything and doesn't get me a function for T with the width.. :( is there a reason I can't say k2=i*k1?
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    Square Hill Barrier, weird question wording

    Ok now the main problem I am having is simplification. Because the second wave function wasn't complex, I got A = C * exp(i*k3*a)/4 * [ exp(a*k2)*(1/k2 + i/k1)*(k2-i*k3) + exp(-a*k2)*(1/k2-i/k1)*(k2+i*k3) ] which I can't simplify using cos and sin since the exponents inside the square...
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    Square Hill Barrier, weird question wording

    OH so Ψ2 = Fexp(k2 * x) + Gexp(-k2 * x) where k2 = -√(10*m) / ħ and then I just do more or less the same process I did earlier when I had Ψ2 as a complex function?
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    Square Hill Barrier, weird question wording

    Ya ok, this is the other issue, I've never dealt with a situation where the total energy E is less than V in a region as it is in region 2 of this case, so how do I get Ψ2? k1 = k3 = √(2mE) / ħ and k2 = √(2m(E-V)) / ħ where E = 5 and V = 10. Lastly, I found A in terms of C through...
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    Square Hill Barrier, weird question wording

    So I have Ψ1 = Aexp(i*k1*x) + Bexp(-i*k1*x) Ψ2 = Fexp(i*k2*x) + Gexp(-i*k2*x) Ψ3 = Cexp(i*k3*x) + 0 the condition I have is that there won't be any particles going from region 3 in the negative x direction right so D is zero. Then I get F and G in terms of C and can use those relations to get A...
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    Square Hill Barrier, weird question wording

    Thanks for replying! So I have a drawing now of a rectangle of 10eV on the y-axis and length "w" on the x-axis, with a horizontal line at height 5eV. Classically forbidden regions sounds very familiar, that's where tunneling comes into play right? When classically a particle can't pass a...
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    Join the Community: Exploring Physics Undergrad Questions

    Found these forums extremely helpful in getting through my first couple years of honors physics undergrad. Thought I'd join up and try to contribute and maybe ask some of my own questions! Thanks!
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    Square Hill Barrier, weird question wording

    Homework Statement Consider a square hill barrier produced by a 10V potential. Incident upon this barrier is a steady stream of 5eV electrons. (a) If half the electrons are transmitted, how thick is the barrier? (Please derive the transmission probability rather than merely quoting it.)...
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