Recent content by crazycool2

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    I  Simplifying Summation Algebra with Differential Equations

    Hi, I'm working with series solutions of differential equations and I have come across something that has troubled me other courses as well. given that \begin{equation} \sum_{n=0}^{\infty} c_{n+2}x^n+e^{-x} \sum_{n=0}^{\infty}c_{n}x^n \\ \text{where}\\...
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    Magnetic field from electric field given a function of time

    Homework Statement An em wave in free space has an electric field vector E = f(t-z/c0)x where x is a unit vector in the x direction and f(t)= exp(-t2/τ2)exp(j2πv0t). Describe the physical nature of this wave and determine an expression of the magnetic field vector. Homework Equations...
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    What's the System Transfer Function H(z) for y[n] = −1/2y[n − 1] + x[n]?

    Z [x (n − n0)] = z-n0X(z); y[n]+1/2y[n-1]=x[n] →y[n+1]0+1/2y[n]=x[n+1] Z-transform and get → z1Y(z) + 1/2z0Y(z)=z1X(z) → (z+1/2])Y(z)=zX(z) given that H(z) = X(z)/Y(z) z/(z+1/2)=X(z)/Y(z)=H(z) I hope this is correct now? though I'm still not getting the initial point part.
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    What's the System Transfer Function H(z) for y[n] = −1/2y[n − 1] + x[n]?

    well in the textbook I'm using it's written Z [x (n − n0)] = z-n0X(z); and if Z(Y[n])= Y(z) then Z(Y[n+1])= z1Y(z) that's gives me y[n]+1/2y[n-1] = z0Y(z) + 1/2z-1Y(z) that's where I go Y(z) = 1+1/2z-1. I don't understand where I am going wrong
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    What's the System Transfer Function H(z) for y[n] = −1/2y[n − 1] + x[n]?

    I'm not so sure about the time shifting theorem, but I used the Transfer function H(z)=Y(z)/X(z). my X(z) is z/(z-a) and I tried Y(z) to be z+1/2 but I'm unsure. after that I supposed to sketch it's Zeros and poles. Am I on the right track?
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    What's the System Transfer Function H(z) for y[n] = −1/2y[n − 1] + x[n]?

    Homework Statement x[n] = anu[n] A discrete system y[n] = −1/2y[n − 1] + x[n]; where x[n] and y[n] in- and output of the system, respectively. Find the system transfer function H(z), and sketch its zeros and poles in the z-plane Homework Equations u[n] is the unit step function...
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    Verify Stokes theorem for the given Surface

    thanx I solved it doing it your by changing to spherical and got 0 on both sides, but the question still remains, is there a theory that says something about if you have an odd function and a symetric surface then the integral is automatically 0. Like no matter what function as long as it's...
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    Verify Stokes theorem for the given Surface

    I've used sperical coordinates on the right side and I get 0 unless I did something wrong, but I'm more concerned about the left side I've changed it a bit but the question still remains, can I just say its = 0 becoz the surface is symmetrical and odd functions have double integral =...
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    Verify Stokes theorem for the given Surface

    Homework Statement verify Stokes theorem for the given Surface and VECTOR FIELD x2 + y2+z2=4, z≤0 oriented by a downward normal. F=(2y-z)i+(x+y2-z)j+(4y-3x)k Homework Equations ∫∫S Δ χ F dS=∫ ∂SF.ds the triangle is supposed to be upside down. The Attempt at a Solution myΔχF =...
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    Loop-the-loop find height object falls out of the loop

    thanx I solved it! I expressed my v as √g r sinθ and my height as r(1+sin(θ) and then put it in the consevation of energy equation! ,but there was a part b) in the question. if you assume the object goes out off the loop at any given P and lands on the loop again at E which is the same height...
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    Loop-the-loop find height object falls out of the loop

    v = sqrt(g r sin (theta)) 0.5mv*v = mg h h= r sin (theta) /2 then i use my equation 1/2* kx^2 = 1/2m g sin (theta) + 1/2mg sin (theta). but i get my 1/2 kx^2 > mgr. should that be possible?
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    Loop-the-loop find height object falls out of the loop

    if I add theta then I will have two unknowns, h and theta, and since now i can find the speed of v at horizontal diameter. mgsin 45=mvv/r but how will it help?
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    Loop-the-loop find height object falls out of the loop

    mg sin(theta) = ma the forces that act are mg downwards and centripetal in the radial direction. then our mg sin must be our normal force which also points in the radial direction,am I going in the right direction?
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    Loop-the-loop find height object falls out of the loop

    that's where I get stuck mixing radial stuff with Newtons laws, but I'm guess you mean v=rω ω= delta(θ)/delta t?
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    Loop-the-loop find height object falls out of the loop

    that's all that is the question, but I tried using Forces. the conditions to stay in the loop on top is mg + n = mv2/r where n=0 because it doesn't touch the loop. then v= √gr but that's just on the top, I don't know how to do it in another random area . the point it let's go it becomes free...
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