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  1. J

    Scaling Pareto between 1 and 0

    Hello and thank you for taking the time to read this. I am making a number generator that generates a number based on a pareto distribution. The problem is, the distribution essentially goes from 0 to infinity. How would I go about scaling the values so I get a range between 0 and 1...
  2. J

    Galois Fields, Grobner Bases, N queens

    Hi all. Thank you for taking the time to read this. I am currently studying Grobner Bases and I've been given a problem that I'm struggling to find any resources for. I am interested in find if a certain n for the n queens problem have solutions. Now there are SAT solvers and such which can...
  3. J

    Complex Number, properties of moduli

    Homework Statement Hello! I'm lost on how to start this, I've got formulas given to me from the text, but I have no idea on how to piece everything together. So I need to use established properties of moduli to show that when \left.\left|z_{3}\right|\neq\left|z_{4}\right|, then...
  4. J

    Fourier transform with mixed derivatives/ 2nd order ODE

    Homework Statement Hi, So I'm suppose to solve the following problem: \left.\frac{d^{2}u}{dt^{2}}-4\frac{d^{3}u}{dt dx^{2}}+3\frac{d^{4}u}{dx^{4}}=0 \left.u(x,0) = f(x) \left.\frac{du}{dt}(x,0) = g(x) Homework Equations The Attempt at a Solution First I use fourier transform on...
  5. J

    Solving for non moving points of a 1-D wave

    Homework Statement Hi! I'm suppose to find the points x on the "string" 1-D wave which are not moving during the vibrations, i.e., 0<x<1 such that u(x,t) = 0 for all times t >0 Homework Equations \left.u(x,t) = sin( \pi x)cos(\pi t) + \frac{1}{2}sin(3\pi x)cos(3\pi t) + 3sin(7\pi x)...
  6. J

    Understanding Graph of a PDE after using D'alambert's wave equation for infinity L

    Homework Statement Hi, so the initial problem was: given \left.\frac{d^{2}u}{dt^{2}} = \frac{d^{2}u}{dx^{2}}} \left.-\infty \leq x \leq \infty \left.u(x,0)=\frac{x}{1+x^{3}} , \frac{du}{dt}(x,0) = 0 Solve the PDE(did this part already) and plot the solution for -20 < x <20 and t =...
  7. J

    Answer check transport equation (1st order linear PDE)

    Homework Statement Hi everyone, I just wanted to double check if I've solved this correctly? Given: \left.\frac{du}{dx} + sin(x)\frac{du}{dy} = 0 \left.-\infty < x < \infty y > 0 \left.u(\frac{\pi}{2} , y ) = y^{2} Solve the PDE Homework Equations Method of characteristics The Attempt...
  8. J

    Proving sums of periodic functions need not be periodic(almost periodic)

    Homework Statement Hi and thank you for reading this! Let \left.f(x) = cos(x) + cos\left(\pi x\right) a) show that the equation f(x)=2 has a unique solution. b) conclude from part a that f is not periodic. Does this contradict withe the previous exercise that states if...
  9. J

    Answer check for a couple fourier series problems

    Homework Statement hello, so I've got a couple of problems I need someone to kind of check over because on one of them, I'm not sure if it's correct, and then the other looks to be incorrect. For problem 1, we have a 2\pi periodic function where f(x) = xsin(x) For the second problem, I...
  10. J

    Solving the coefficients of fourier series

    Homework Statement f(x) = |cos x| if -\pi \leq x \leq\ \pi The fourier series answer we should end up with is the following: 2/\pi - 4/\pi\sum\frac{-1^{k}}{(2k)^{2}-1}cos(2kx) where for the summation, k = 1 and goes to infinity. What I need to do is to actually go an solve for the...
  11. J

    C# deleting picture boxes when it reaches certain location

    Homework Statement Hi, for our homework, we have to create a billiard game with c#. What I need help is when the picture box (containing a picture of a ball) reaches one of the pockets, how do I remove it from the form/program? Is there some kind of delete keyword I can use or will I have to...
  12. J

    Reduction of PDE to an ODE by means of linear change of variables

    Homework Statement So it's been a really long time since I've done any ode/linear algebra and would like some help with this problem. Derive the general solution of the given equation by using an appropriate change of variables 2\deltau/\deltat + 3\deltau/\deltax = 0 The thing that...
  13. J

    Boltzmann statistics - finding the number of particles

    Boltzmann statistics -- finding the number of particles Homework Statement A column of water contains fine spherical metal particles of radius 2 x10-8m, which are in thermal equilibrium at 25C. If there are 1000 particles per unit volume at a given height, how many particles would be found...
  14. J

    Relativistic dynamics of high energy particles

    Homework Statement a) a photon of energy E = 2m0c2 hits a resting particle of rest mass m0 and is absorbed by it. What is the subsequent speed of the new particle after absorption b)Protons have been observed with energies of up to 1021 eV. How thick does Earth appear to the proton? c)...
  15. J

    Fizeau experiment problem,

    fizeau experiment problem, urgent Homework Statement A beam of monochromatic light, whose wavelength in free space is lambda, is split into two separate beams and each is then passed through identical troughs of water. The speed of light in a medium is given my v = c/n, where n is the...
  16. J

    Relativistic Timing

    Homework Statement A member of a colony on Jupiter is required to salute the UN flag at the same time as it is being done on Earth at noon in New York. If observers in all inertial frames(i.e. any observer traveling at any arbitrary velocity) are to agree that he has performed his duty, how...
  17. J

    Relativistic rockets answer check

    Homework Statement Two Rockets A and B depart from Earth at constant speeds of 0.6c in opposite directions, having synchronized clocks with each other and with Earth at departure. After one year as measured in Earth's reference frame, rocket B emits a light signal(call this event E1). At...
  18. J

    Relativistic train problem

    Homework Statement A train moves past a tower at a speed of 0.78c. The train has a rest length of L' = 450m. When the front of the train passes the tower, the clocks in the tower and in the front of the train are synchronized to t=t'=0s. The instant that the back of the train passes the...
  19. J

    Another relativity question check =P

    Homework Statement It seems this question is a little too easy? I'm a little skeptical so could someone please do a quick check for me? The pion is an elementary particle that decays with a mean lifetime in its rest frame of 2.6x10^-8s. A beam of pions has a speed of 0.79c. a) In the...
  20. J

    Special relativity question check

    Homework Statement A passenger in a train moving at 30m/s passes a person standing on a station platform at t= t' =0. Twenty seconds after the train passes, the person on the platform determins that a bird flying along the tracks in the same direction as the train is 800m away. Five seconds...
  21. J

    Quick dimensional analysis question check

    Hi, I haven't looked at math/physics in awhile and want to make sure I did this correctly lol Homework Statement The viscosity of a gas depends on the mass(m), the effective diamtere(d) of the gas and the mean speed(v) of the gas molecules. The unit of viscosity is (pascal * second). use...
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