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    Basic crystal oscillator specifications question

    Ahh yes that looks like it could be useful. Since I don't really have many requirements other than generating a clean clock signal overkill is probably fine. I guess will probably just buy a few components and try to see what works best.
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    Basic crystal oscillator specifications question

    I need to create a 10 MHz square wave clock signal which gets terminated into a 50 ohm resistor for use by a waveform generator. The specifications for the waveform generator suggest a 12 to 14 dBm power level for the input clock. ie. a power level of ~16-25mW. So I've been looking to...
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    Oscilloscope trigger timing issue?

    I've adjusted probably every setting on my oscilloscope and triggered on rising and falling edges and I have also tried it with the 50 ohm terminations removed. Also it is just a simple sma connection from the waveform generator to the oscilloscope with the terminations connected with a bnc...
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    Oscilloscope trigger timing issue?

    I'm using coaxial/sma connectors and the terminations are coaxial terminations. I'll check out a square wave tomorrow but if jumping due to the trigger is only supposed to be around 10 ps then it seems like it probably is the waveform generator. Which at least narrows it down. There are some...
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    Oscilloscope trigger timing issue?

    I'm using an arbitrary waveform generator that is generating a 1 MHz ramp waveform. I'm triggering on a marker sent out by the waveform generator which is tied to the same memory location as the start of the waveform. So although there is supposed to be a small latency (1-3ns) between the...
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    A funny proof, but what is wrong with it?

    The assumption that for all possible integers n, n!>[(n+1)/2]^n is violated by your counter example, so that demonstrates that your assumption is false. You have not checked all possible values of n so it says nothing about any of those values. Your assumption being false says nothing about...
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    Stern Gerlach expectation value

    1. Homework Statement An electron starts in a spin state |\psi(t=0)\rangle = |z \uparrow \rangle and evolves in a magnetic field B_0(\hat{x} + \hat{z}). The Hamiltonian of the system is \hat{H} = \alpha \vec{B}\cdot\vec{S}. Evaluate \langle \psi (t_{1/2}) | S_x | \psi(t_{1/2}) \rangle...
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    Branch cut of the principle value log

    1. Homework Statement Find the branch points of g(z) = log(z(z+1)/(z-1)) and defining a branch of g as the principle branch of the logarithm find the location of the branch cuts. 2. Homework Equations 3. The Attempt at a Solution Since g(z) = log(z) + log(z+1) - log(z-1) the branch...
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    Cross product

    Try defining each vector (a_1, a_2, a_3), (b_1, b_2, b_3), (c_1, c_2, c_3) and then using the defintion of the cross product in each case.
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    Stokes theorem application

    1. Homework Statement Let F(x, y, z) = \left ( e^{-y^2} + y^{1+x^2} +cos(z), -z, y \right) Let s Be the portion of the paraboloid y^2+z^2=4(x+1) for 0 \leq x \leq 3 and the portion of the sphere x^2 + y^2 +z^2 = 4 for x \leq 0 Find \iint\limits_s curl(\vec{F}) d \vec{s} 2...
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    Hooke's law sanity check

    Thanks, I can solve the rest of it pretty easily now. I think I was just over thinking which springs were pulling where.
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    Hooke's law sanity check

    1. Homework Statement 4 springs with a mass on each end are connected in series as below: | | | | m1 | | | | m2 | | | | m3 | | | | m4 All the masses are mass m, the length of each spring is 1, and the spring constant is k, find the extension of each spring. 2...
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    Protoboard circuit setup

    Well I went into the lab, and now that I have a better understanding of how the ground connections work I found several other ground connections on the other end of the protoboard so it became pretty straight forward to set up several things in parallel with the coaxial cables. I knew it had to...
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    Protoboard circuit setup

    Thanks for your help, I'm going to stop by the lab tomorrow and play around with the circuit so I'll post after that.
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    Protoboard circuit setup

    Yeah that makes sense, in that case would the second drawing I made with the three ground connections represent the circuit you're talking about?
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    Protoboard circuit setup

    I think we are supposed to construct the circuit using the BNC connectors, and our TA suggested we connect the voltmeter in that fashion so It can be done. I don't even think we were provided with cables to form a direct connection across the resistor with the voltmeter. I may be able to find...
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    Protoboard circuit setup

    On the diagram you drew I could construct the circuit fine because there are clear positive and negative terminals for each item, but I can't see those on the protoboard I'm using.
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    Protoboard circuit setup

    No it doesn't. Here is a picture of the actual protoboard, sorry it isn't closer
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    Protoboard circuit setup

    I was under the impression that since that the voltmeter, ammeter and function generator all connect with a single cable (which contains the positive lead inside, and the negative lead or ground on the outer metal jacket of the cable) to the protoboard unit that each object has a separate ground...
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    Protoboard circuit setup

    You mean like in the picture i drew below? Doesn't that put the ammeter + resistor in parallel with the voltmeter?
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    Protoboard circuit setup

    Isn't the ammeter connected right at the negative 'end' by the grounds though?
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    Protoboard circuit setup

    1. Homework Statement Sorry if this is in the wrong forum, but it is for an introductory lab course. I am trying to set up the simple circuit in part A of my drawing on a protoboard containing the components in part B of my drawing. 2. Homework Equations n/a 3. The Attempt...
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    Neumann BVP steady state solution

    Separation of variables along with eigenfunction expansion are the only methods i have learned for solving PDEs as of yet, so maybe I just haven't learned the proper method for this question. The solution I have uses separation of variables, but I'm just questioning why you can use separation...
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    Neumann BVP steady state solution

    1. Homework Statement U_t = u_{xx} - 4U u_x (0, t) = 0, u_x (\pi, t) = 1 u(x, 0) = 4cos(4x) Find a steady state solution to the boundary value problem. 2. Homework Equations n/a 3. The Attempt at a Solution Well i'm quite comfortable solving dirichlet/ mixed boundary...
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    Parallel vectors

    Assuming you're trying to find which values of a make the two vectors parralell... the k-hat component isn't right in what you've posted, and once you get that it's pretty straightforward to find the values of a so that's you get the zero vector as the cross product.
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    Linear ODE Solution Existence

    The theorem only guarantees that for a given initial value, if the 'standard form' functions (like the form you have the ODE in) are continuous for a given initial value, then a unique solution is guaranteed to exist, and the solution is guaranteed to be valid on the interval of continuity that...
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    Variation of parameters ODE what am i doing wrong?

    ahh yep that would be wrong. I did the after correcting that mistake and got the correct answer. I guess i just keep making computational mistakes somewhere along the way. Thanks for the derivation of Diagonalization, that was much clearer than the one in my textbook, and it definitely...
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    Variation of parameters ODE what am i doing wrong?

    1. Homework Statement \mathbb{x'}= \begin{bmatrix} 1 & 1 \\ 4 & 1 \end{bmatrix} \mathbf{x} \ + \ \begin{bmatrix} 2e^{t} \\ -e^{t} \end{bmatrix} Find the general solution. 2. Homework Equations 3. The Attempt at a Solution Well i found the eigenvalues of the matrix That...
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    System of ODEs independent solutions

    yes well looking at it now it definitely is almost trivial. I'm just a little hazy as to what constitutes an indepedent solution to a system of equations I guess.
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    System of ODEs independent solutions

    hmmm ok, I that makes enough sense, though need to do some more reading. Can you compute the wronskian as the determinant of the matrix of the spanning vectors, ie. W = e^{4t} \neq 0
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