Recent content by snickersnee

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    For a string with fixed ends, which normal modes are missing?

    Homework Statement Here's the problem. I was able to find the a_n and b_n values, my question is mainly on part (c), how do I find which modes are missing? The function is odd, so even modes should disappear, but cos(n*pi) doesn't disappear, it's either +1 or -1. I'd greatly appreciate any...
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    Pressure standing wave pattern, change cross sectional area

    Hi thanks for responding. Here are the formulas for the reflection and transmission coefficients: where S1, S2 are cross sectional areas. R=1 if S2<<S1, a sudden strong area contraction almost acts as a rigid wall. R=-1 if S2>>S1, in this case the junction acts almost as a pressure-release...
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    Pressure standing wave pattern, change cross sectional area

    Homework Statement See pictures. There are 2 parts to the problem but I can probably figure out the second part once I get the first part. [/B] Homework Equations Antinodes (minimum pressure) at Nodes (maximum pressure) at [/B] Equation for a standing wave: The Attempt at a Solution...
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    Time averaged intensity, derivation and vector plot

    Homework Statement I'm trying to graph this equation: [/B] I'm trying to use the champ command in scilab to graph this from -π to π on the kx and ky axes. But this requires the x and y components of the vector as arguments. How do I get those components, is there a command for that? There's...
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    How Does the Energy of a Struck String Change Over Time?

    Homework Statement An undisturbed string is struck from below by a hammer of width 2a, as shown in the figure. Calculate the total energy of the wave motion and show that it is equal to the energy the string has when it is first struck 3 cases: t=0+ (string just got struck) t>(a/c) (when...
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    How Does Tsunami Wavelength Affect Particle Displacement and Wave Equation?

    Homework Statement Wavelength of a tsunami: Propagates toward shore as a sinusoidal plane wave. - determine the peak value of the horizontal particle displacement. Is your answer consistent with the assumption that the water momentum is mainly horizontal? Explain by considering the...
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    Behavior of strings with displacement in the middle

    Homework Statement [/B] I have a string that's infinite on one side, as well as a string that's infinite on both sides. The displacement at the center (x=0) is the same for both, as shown in the pictures. Homework Equations [/B] I think the G term goes to 0 because there's no incoming wave...
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    Wave speed of the collision process in a line of cars

    Thanks for your help. I think the time should change for longer cars because the disturbance takes longer to pass through that car, assuming the velocity of the disturbance is constant. And you're right, I should flip the fraction so it becomes
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    String gets deformed and released - derive equation

    Thanks for your response. But I have to graph it too, what would be some good times to plug in? And how do I make the characteristics diagram?
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    Wave speed of the collision process in a line of cars

    Yes we're assuming elastic collisions. The first bumped car is traveling at v0 because the car behind it transferred all its energy. The time until the next collision is . I was thinking the total distance would be (4L+3x) and total time would be 3v0/(L+x) but then (total distance)/(total time)...
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    String gets deformed and released - derive equation

    Homework Statement [/B] This graph shows an infinite string on the x-axis. The middle part is deformed as shown. The string is released at time t=0 - give the analytical solution of the problem, i.e. find for t>0 - sketch the string displacement \xi(x) for a sequence of times t. (I'd like...
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    Wave speed of the collision process in a line of cars

    Homework Statement I need to write an equation for the at rest at a stoplight. Each car bumps into the one in front of it until the first car in line gets bumped. Homework Equations I found these equations for wave speed: V=√(T/(m/L)), where T is tension, m is mass, L is length and of...
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    Program that counts all the vertices in a given tree

    Homework Statement "Write a program that counts all the vertices in a given tree." Any language can be used. (I've been using Perl mostly but could do C too. C++ would be ok too, if it was significantly easier.) Homework Equations I've been trying to find this. I read if a tree has n...
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    Kramers-Kronig Mathematica code

    Homework Statement I'm trying to write Mathematica code to use Kramers-Kronig on a csv file with 2 columns. Column 1 is h(eV). It goes from 0 to 6, in increments of 0.1. Column 2 is alpha (cm^-1). In the equation below, I'm guessing column 1 is Ω. But what should I put in for ω?Homework...
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    Photon conservation in Raman amplification

    Part 1: Homework Statement Use two coupled-wave equations for the Raman amplification process depicted to the right to show that for every photon at Stokes frequency omega_s created (destroyed) one photon in the laser pump field omega_L is destroyed (created). I have the coupled-wave...
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