Recent content by the7joker7

  1. T

    Question about the velocity of a wave

    Homework Statement If you are given the length of a rope as 8 meters (and the g/m of the rope as 69, and impact strength of the type of rope it is as 8.8kN) and the tension in the rope when stretched out as 418N, how do you find the velocity of a pulse that creates a 1mm vertical...
  2. T

    Finding the spiral sinks and spiral sources of a linear system

    For the most part, I understand the relationship between behavior and eigenvalues. When you have two positive eigenvalues it's a source, two negative it's a sink, so on and so forth... My issue is, what's the easiest way to find for which values of A and B are there complex values involved.
  3. T

    Finding the spiral sinks and spiral sources of a linear system

    Homework Statement Basically, the problem involves a linear system dx/dt = ax + by and dy/dt = -x - y, with a and b being parameters that can take on any real value. Basically, you go through this system for several values of a and b (I did -12 to 12) to find the state at various points...
  4. T

    Electric Potential Difference Question (Parallel plates, higher potential)

    Homework Statement I have two large parallel plates that are conducting and separated by 10.0cm. The charges on the plates are uniform and equal in magnitude but opposite in sign. The difference in potential between the two is 500 V. The first question concerning this is which plate...
  5. T

    Finding the first-order taylor polynomial

    Homework Statement Basically, I have a differential equation. One of the elements of it is... F(P) = 0.2P(1 - (P/10)) And I need to replace it with it's first-order Taylor polynomial centered at P=10. The Attempt at a Solution I haven't done Taylor polynomial stuff in over a...
  6. T

    General Solution to the Diff. Eq. dy/dt = ty

    y dy = (t dt)/(t^2 + 1) y^2/2 = (t dt/t^2) + t dt (If I understand correctly, this is separating?) y^2/2 = ((t^2)/2)/t^2 + t^2/2 y^2/2 = 1/2 + t^2/2 y^2 = 1/4 + t^2/4 y = sqrt(k(.25 + t^2/4)) Eh?
  7. T

    General Solution to the Diff. Eq. dy/dt = ty

    Lesse dy/dt = t/((t^2)y + y) dy/y = t/((t^2)y^2 + y^2) dt dy/y * y^2 + y^2 = t/(t^2) dt dy/y * 2(y^2) = 1/t ln(y) * 2(y^3/3) = 1/t Ugh...I dunno, something in that ballpark? I'm confused...
  8. T

    General Solution to the Diff. Eq. dy/dt = ty

    Oops, my bad. It's the 2nd one. dy/dt = t/((t^2)y + y)
  9. T

    General Solution to the Diff. Eq. dy/dt = ty

    Just to be sure, is the basic starting step for all problems of this type getting dy/y? Like if I have the same question with dy/dt = t/(t^2y + y), I would try to get dy/y on one side?
  10. T

    General Solution to the Diff. Eq. dy/dt = ty

    log(y) = t^2/2 So y = e^(t^2/2) Alright. And the k is because it's a general equation and k needs to be there so it can be solved for any initial condition. But why is the k being multiplied and not added?
  11. T

    General Solution to the Diff. Eq. dy/dt = ty

    dy/y = t dt The integral of that would be... dy = t^2/2 So (t^2/2)/dt = ty t^2/2 = ty dt Where do I go from here?
  12. T

    General Solution to the Diff. Eq. dy/dt = ty

    Homework Statement Find the general solution of the differential equation specified. \frac{dy}{dt} = ty. The Attempt at a Solution I already know the answer to be ke^{t^{2}/2}, but can't figure out how it got here. I'm rusty with my integrals and am just really starting diff eqs...
  13. T

    Finding the Sum of a Series: e^{(n+1)/n}- e^{(n+2)/(n+1)}

    Lemme see here... The series is indeed telescoping and I have it simplifying to... ((2^k)/k!) - (((n + 2)/(n + 1))^k)/k! Since n + 2 over n + 1 will run to 1... ((2^k/k!) - ((1^k/k!)) So... 1^k/k! Am I on the right track?
  14. T

    Finding the Sum of a Series: e^{(n+1)/n}- e^{(n+2)/(n+1)}

    Ohhh...I see. So, what is k supposed to be? Is it just a variable, or does it get a value?
  15. T

    Finding the Sum of a Series: e^{(n+1)/n}- e^{(n+2)/(n+1)}

    Very close! But, alas, putting numbers in for n for the first three terms gives... (2 - 1.5) + (1.125 - .88889) + (.39506 - .3255208) The powers are throwing it off...
Back
Top