Recent content by CrosisBH

  1. CrosisBH

    I What does an uncertainity of 0 mean?

    I'm just starting my undergraduate Quantum Mechanics course. I had a homework problem to show that \Delta S_x = \sqrt{\langle S_x^2 \rangle - \langle S_x \rangle ^2} = 0 , S_x being the spin in the x direction. I managed to solve it, but the physical interpretation is confusing me. If I...
  2. CrosisBH

    Maximizing the volume of a cylinder

    Note this is in our Lagrangian Mechanics section of Classical Mechanics, so I assume he wants us to use Calculus of Variations to solve it. The surface area is fixed, so that'll be the constraint. Maximizing volume, we need a functional to represent Volume. This was tricky, but my best guess for...
  3. CrosisBH

    Computing the wave function of a square potential

    I changed how the potential is handled with a simple function def potential(x): if (abs(x)<=1): return 0 else: return V0 So now my stepping function is Which surprisingly yielded the same plot. I will look into starting at x = 0. Will come back with updates.UPDATE: I...
  4. CrosisBH

    Computing the wave function of a square potential

    Every one of those would represent the first point in the list, corresponding to the very left of it's domain. wavefunction[0] and x_axis_wave[0] correspond to the their function at -1, while with potential and it's domain's 0th element is their function at -3. I have constructed the lists so...
  5. CrosisBH

    Computing the wave function of a square potential

    The book's procedure for the "shooting method" The point of this program is to compute a wave function and to try and home in on the ground eigenvalue energy, which i should expect pi^2 / 8 = 1.2337... This is my program (written in python) import matplotlib.pyplot as plt import numpy as...
  6. CrosisBH

    Trouble with Electric Potential Boundaries (Computational Physics)

    This is in python: #ELECTRIC POTENTIAL from mpl_toolkits.mplot3d import Axes3D from matplotlib import cm import numpy as np import matplotlib.pyplot as plt dx = 0.1 dy = 0.1 xrange=np.arange(-1,1,dx) yrange=np.arange(-1,1,dy) X,Y = np.meshgrid(xrange, yrange) max_dV = 10e-5 blockRadius = 3...
  7. CrosisBH

    Finding the final velocity with quadratic drag

    Okay it turns out I was making a fatal error. These damn negative signs. The second differential equation yields $$\frac{-v_t^2 \ln\left(\frac{v_t^2-v_f^2}{v_t^2}\right)}{2g} = -y_{max}$$. I forgot cancel negatives and dropped it when i subbed y_max. A lot of canceling yields...
  8. CrosisBH

    Finding the final velocity with quadratic drag

    I chose coordinates where down is positive. So the force going up is $$F_{up} = mg - cv^2$$ $$a = g + \frac{c}{m}v^2$$ $$a = g + \frac{c}{m}v^2$$ $$a = g \left(1 + \frac{v^2}{v_t^2}\right)$$ $$a = \frac{dv}{dt} = v\frac{dv}{dy} = g \left(1 + \frac{v^2}{v_t^2}\right)$$ I used normal separation of...
  9. CrosisBH

    [Computational Physics] Modeling the path of a Baseball with drag

    Damn, that was the problem! I went ahead and each 6 arrays and added their 0th component by hand, and now the plot is display (roughly) what I need! Just need to clean it up a bit.
  10. CrosisBH

    [Computational Physics] Modeling the path of a Baseball with drag

    import matplotlib.pyplot as plt import numpy as np #constants and conditions initial_velocity = 49.1744 #m/s, book has 110mph velocity_angle = 35 * np.pi / 180 #coverted to radians because numpy only likes radians gravity = 9.8 #m/s^2 dt=0.1 windspeed = 4.4704 #m/s book has 10mph #calculating...
  11. CrosisBH

    Courses Taking both Classical Physics and Quantum Physics at the Same Time.

    Sorry I confused myself when making this thread. I was tired. I should also specify the level of the course too. Quantum Physics I is the course name, but the other course is Classical Mechanics I. As for textbooks, I haven't figured out my Quantum book but I know for Classical Mechanics it's...
  12. CrosisBH

    Courses Taking both Classical Physics and Quantum Physics at the Same Time.

    They simply said "You're going to have to do this if you want to graduate in 2021" They're the one that suggested I do it.
  13. CrosisBH

    Courses Taking both Classical Physics and Quantum Physics at the Same Time.

    Hello! I'll be entering my second semester of my junior year of my Physics Degree. My uni doesn't have a bad physics program, but it's really small so I have to take my upper level classes as soon as they're offered or I won't take them for another 2 years or so. They are on a cycle so I will be...
  14. CrosisBH

    I Why does this needle get an E field while this disk gets a D field?

    So I'm reviewing old lectures to prepare for an exam soon. This is about polarization. E fields, D Fields, etc. My professor labeled this diagram like so. The figures my professor drew are cavities in a dielectric if you can't read her handwriting. However, I can't seem to figure out why the...
  15. CrosisBH

    I Solving an ODE with Legendre Polynomials

    From Griffiths E&M 4th edition. He went over solving a PDE using separation of variables. It got to this ODE \frac{d}{d\theta}\left(\sin\theta\frac{d\Theta}{d\theta}\right)= -l(l+1)\sin \theta \Theta Griffths states that this ODE has the solution \Theta = P_l(\cos\theta) Where $$P_l =...
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