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classes:2009:fall:phys4101.001:q_a_1021

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classes:2009:fall:phys4101.001:q_a_1021 [2009/10/22 23:32] – elyclasses:2009:fall:phys4101.001:q_a_1021 [2009/10/23 10:34] (current) – jbarthel
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 === Dark Helmet 10/22 === === Dark Helmet 10/22 ===
 Depending on your degree of sarcasm, i am either just as excited as you or much less excited than you. :) Depending on your degree of sarcasm, i am either just as excited as you or much less excited than you. :)
 +
 +===Captain America 10-23===
 +I'm pumped!
  
 ====Hydra==== ====Hydra====
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 ===Spherical=== ===Spherical===
 Maybe, as Griffiths says, I shoulda been a mathematician...  I realize he's not explicitly mentioning a delta function, it just sounds like what he refers to "could be" a delta function as well...  but ya.  It's just not. Is a delta function "square integrable"? -- Yes because it has an 'area' yes?   Maybe, as Griffiths says, I shoulda been a mathematician...  I realize he's not explicitly mentioning a delta function, it just sounds like what he refers to "could be" a delta function as well...  but ya.  It's just not. Is a delta function "square integrable"? -- Yes because it has an 'area' yes?  
 +
 +===liux0756===
 +The 'isolated points' the footnote related is talking about points with finite values. Of course delta function is not square integrable, because <math>\int_{-\infty}^{+\infty} \delta(x)^2 dx = \int_{-\infty}^{+\infty} \delta(x) \delta(x) dx =\delta(0) = + \infty </math> (equation [2.113])
  
 ====Daniel Faraday 10/22 10:30pm==== ====Daniel Faraday 10/22 10:30pm====
 So, for the finite square well problem in the sample quiz, we are asked to calculate the first two values of //l//. Is this doable without a computer? If so, how? So, for the finite square well problem in the sample quiz, we are asked to calculate the first two values of //l//. Is this doable without a computer? If so, how?
  
 +===Green Suit 10/23 8:00===
 +I think this is as simple as looking at the graph provided and looking for where the lines cross. For symmetric z= 2, 4 (approximately) with z=la then l= 2/a, 4/a. For asymmetric z= 3, 5 (approximately) then l= 3/a, 5/a. I think. It's then up to you to figure out if those numbers are sensible.
  
 ====Sherical chicken==== ====Sherical chicken====
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 The answer is "Alpha is real".  isn't this contradicting what we  were told to assume?   The answer is "Alpha is real".  isn't this contradicting what we  were told to assume?  
  
 +===Daniel Faraday 10/23 730am=== 
 +It doesn't say that <math>\alpha</math> is imaginary, it says that it is //complex//. So it can be represented by <math>\alpha = a + bi</math>. So you solve the problem to find that <math>b=0.</math>
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 **Q&A for the previous lecture: [[Q_A_1019]]**\\ **Q&A for the previous lecture: [[Q_A_1019]]**\\
 **Q&A for the next lecture: [[Q_A_1023]]** **Q&A for the next lecture: [[Q_A_1023]]**
classes/2009/fall/phys4101.001/q_a_1021.1256272358.txt.gz · Last modified: 2009/10/22 23:32 by ely

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