Recent content by Yggdresil

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    Programs Environmental Solutions and Semiconductors: Research Interests and Career Goals

    Just out of curiosity, you have checked that the REU is open to non-US citizens? Some are not. Unless you are a US citizen, then feel free to ignore this. Advice: Take your rough draft to your universities writing center, they’ll be able to help you fix a lot of the grammar issues you have...
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    Electrical UHF/SHF Electromagnet Homework Solution

    So you want to cloak the time varying b-field by changing its path geometry at some radio frequency and allow the time varying e-field to pass unmolested? I’m confused by the second part , since the form of Maxwells equations won’t change form with geometric transformations. A change in geometry...
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    Electrical UHF/SHF Electromagnet Homework Solution

    If it hasn’t been built in practice that’s one thing, I don’t know, but those are engineering/material science problems, not physics problems. Which is vastly different then “the theory doesn’t really work for optical frequencys.” I know optical cloaking has been done with classical lenses in...
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    Electrical UHF/SHF Electromagnet Homework Solution

    The paper does work at optical frequency, or any other frequency. As far as I could tell last night it was a natural extension of Pendrys work:http://science.sciencemag.org/content/312/5781/1780 Which is why it got published.
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    Electrical UHF/SHF Electromagnet Homework Solution

    Here’s were the arxiv paper was published: https://journals.aps.org/prl/abstract/10.1103/PhysRevLett.102.253902
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    Electrical UHF/SHF Electromagnet Homework Solution

    So I’m no expert on transformation optics by any stretch of the imagination, but what I think you’re saying here is that you want to test or create a single negative metamaterial, with ##\mu r<0##. These are called electromagnetic metamaterials. So maybe that’s where your insistence on...
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    Electrical UHF/SHF Electromagnet Homework Solution

    Warning: magnetrons in microwaves may or may not contain beryllium oxide, which could lead to chronic illness and death if breathed in. You also have concerns about high voltage. If you don’t know what you’re doing, don’t. A magnetron in consumer microwaves probably operates in S-band, around...
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    Integral Test: Analyzing $$\sum_{n=3}^{\infty} \frac{1}{n^2-4}$$

    That’s a good point, I saw something that looked like a trig substitution , and got blinded by that route. Yeah, however it was just one of those exercises that explicitly stated the method to be used. I’m not sure if using a comparison would have been following “the spirit of the problem”...
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    Studying What books are good to learn the math in intro physics?

    Other than vectors none of this sounds like a math problem. Any introductory mechanics text should have enough information on vectors to avoid the need to consult a math linear algebra textbook. Then you just need to practice. For the rest of it, it certainly sounds like a failure to understand...
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    Integral Test: Analyzing $$\sum_{n=3}^{\infty} \frac{1}{n^2-4}$$

    Ohh, let me run through it again. Thanks!
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    Integral Test: Analyzing $$\sum_{n=3}^{\infty} \frac{1}{n^2-4}$$

    You’re right of course, I misspoke. Doesn’t the sub of ##n = 2\coth \theta## produce ##-\frac{1}{2}\coth^{-1}(\frac{2}{n})## which still has an imaginary component? Using Fresh_42’s or your recommendation of partial fractions I can solve it in terms of logs...
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    Integral Test: Analyzing $$\sum_{n=3}^{\infty} \frac{1}{n^2-4}$$

    Thanks for the help, I’ll give that a go.
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    Integral Test: Analyzing $$\sum_{n=3}^{\infty} \frac{1}{n^2-4}$$

    Homework Statement Use the integral test to determine whether $$\sum_{n=3}^{\infty} \frac{1}{n^2-4}$$ converges or diverges.The Attempt at a Solution [/B] Taking the integral we have $$\int_{}^{\infty}\frac{dn}{n^2-4}$$ Note: Mary Baos text is having us write the integrals without lower bounds...
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    Schools Which colleges in Kentucky would you recommend for physics?

    I went to UKY for a project spring through the summer 2018, they’re generally a good school for physics and most of the faculty were nice and knowledgeable. A few points at UKY: Their upper division physics classes are normally almost all during the morning. That is, most start around 8 or 9...
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