Recent content by eku_girl83

  1. E

    Aerodynamics - Standard Atmosphere problem

    Here's the problem: We are ascending in an elevator at sea level. Our eardrums feel a 1 percent decrease in pressure per minute. Calculate the upward speed of the elevator. My solution: *I am using the equation p1/p0 = (T1/T0)^(-g/aR), where p1 and p0 are pressure at point 1 and point 0...
  2. E

    Parachute deployment (non-instantaneous)

    Here's the problem... A car of mass 2000 kg, drag coefficient .3, frontal area 1 sq. meter releases parachute of area Pi sq. meters (diameter 2 m). The inital velocity of the car is 100 m/s. Calculate distance and velocity after 10 seconds. I know how to work this problem for...
  3. E

    Strength Coefficient and Strain-Hardening Exponent

    Here's the problem: A metal is deformed in a tension test into its plastic region. The starting specimen had a gage length = 2.0 in and an area .50 sq. in. At one point in the tensile test, the gage length = 2.5 in and the corresponding engineering stress = 24000 psi; at another point in the...
  4. E

    Finding a research interest/project

    Now that I'm a research assistant at graduate school in mechanical engineering, I'm having trouble finding precisely where my research interests lie. At least part of my problems stem from the fact that my undergraduate degree is in physics, not engineering. Here are the...
  5. E

    How Do Airy Function Roots Determine Photon Energies in a Gravitational Field?

    The situation involves a neutron in a constant gravitational field (g=9.8). I need to find the energies of photons that transition to the excited state. I solved the Schrodinger equation by doing a variable transformation using Airy functions. To fully solve, however, I need to find the roots...
  6. E

    Calculating Probability for Harmonic Oscillator States

    The psi (x,0) is defined from -x0 to x0 in the problem. Do I still integrate over all space?
  7. E

    Calculating Probability for Harmonic Oscillator States

    I have the U(x) functions for the ground state and first excited state of the simple harmonic oscillator. I also have the psi (x,0) wave function for this situation. How do I find the probability the particle is in a particular state? Is it simply the integral of psi(x,0) * u(x) dx evaluated...
  8. E

    Power Series Solution to Hydrogen Wave Function Differential Equation

    If I sub in C= L(L+1), then I get a2 = -l(l+1)a0/2. But this is the solution for l = 0...so if I let l = 0, then I get a2 =0. This is also true for a3, a4, a5, ... Is this ok? Also...when I normalize...Do I do the integral of a2^2 from -1 to 1 = 1 (since x = cos theta) and solve for a0...
  9. E

    Power Series Solution to Hydrogen Wave Function Differential Equation

    I solved the differential equation for theta portion of the hydrogen wave function using a power series solution. I got a sub n+2 = a sub n ((n(n+1)-C)/(n+2)(n+1)). I then truncated the power series at n = l to get C= l(l+1). I know need to use the recursion formula I found to find the l =...
  10. E

    How Do I Solve the Particle in a Box Problem with Extended Boundaries?

    O.k. I posted earlier concerning this question. I think I know have a better understanding of what's going on. Particle in a box with boundaries at x=L and x=3L. U(x) = A cos kx + B sin kx Applying boundary conditions, I get that 0 = A cos kL + B sin kL and that 0 = A cos 3kL + B sin...
  11. E

    How Does Particle Behavior Change in a Shifted Infinite Square Well?

    Any help is much appreciated!
  12. E

    Help with quantum problem (gravitational field)

    I need to find the energy spectrum for the energes of photons that end up in the 1st excited state from a neutron in a gravitational field of strength g (9.8). I suppose first I need to find an expression for U(x) and substitue into the Schrodinger equation? How do I know U(x)? We have been...
  13. E

    Question concerning particle in a box

    I need to find the probability density function for a particle in a box of width L. The initial state is 1/sqrt(2) u1(x) + 1/sqrt(2) u2(x), where u1(x) is the ground state and u2(x) is the first excited state. Omega is E2-E1/h If I square this wave function, I get 1/2 u1(x)u1(x) +1/2 u2(x)...
  14. E

    Fortran Help with simple Fortran program

    I need to write a program that will print the prime factorization of a number. Here's what I have so far: integer:: n,i print *, "enter integer" read *, n do while (n>1) i=2 if (mod(n,i)==0) then print *, i n = n/i else i = i+1 end if end do end program I'm just...
  15. E

    Driven, damped harmonic oscillator - with particular solution

    Driven, damped harmonic oscillator -- need help with particular solution Consider a damped oscillator with Beta = w/4 driven by F=A1cos(wt)+A2cos(3wt). Find x(t). I know that x(t) is the solution to the system with the above drive force. I know that if an external driving force applied...
Back
Top