Recent content by Andy13

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    RC circuits and potential difference

    Got it, thanks! I missed the importance of defining where zero voltage was. And I did use Kirchhoff's; it was, as you say, a roundabout way to do it that got me the right answer but left me confused. Thanks again!
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    RC circuits and potential difference

    Homework Statement Circuit is at this link: http://www.colorado.edu/physics/phys1120/phys1120_sp08/hws/capa8_figs/gian1946.gif 1. What is the potential at point a with S open (let V=0 at the negative terminal of the source, and assume it's a long time after the circuit was connected to the...
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    Calculating Induced Current in an Expanding Loop

    Should be -d(flux)/dt = integral (B*dA) the derivative of an integral of an equation with respect to t is just B*dA So my mistake was to forget to differentiate at all. Whoops. A = ∏r^2 but r= ro(1+at^2) so dA = derivative of ∏(ro(1+at^2)^2 = 4∏*a*t*ro(1+at^2) EMF = B*4∏*a*t*ro(1+at^2) Does...
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    Calculating Induced Current in an Expanding Loop

    Homework Statement Imagine a pliable round metal loop that can expand or contract. In a region with a constant magnetic field B0 that is oriented perpendicular to the plane of the loop, suppose that the loop expands, with its radius growing with time as r = r0(1+at2). As the loop expands and...
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    Circuits: What does the voltmeter read?

    Homework Statement A E = 12.0V battery with an internal resistance r = 1.80Ohm is connected to two 8.80kilo-Ohm resistors in series. An ammeter of internal resistance 0.410Ohm measures the current exiting the battery and at the same time a voltmeter with internal resistance 17.7kilo-Ohm...
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    Electric Field/ infinite charged sheet

    Thanks SammyS-- I'm glad I wasn't misunderstanding something.
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    Electric Field/ infinite charged sheet

    Homework Statement There are three charged sheets with various charge densities. The following link shows a diagram, and solutions (not mine; these are some professor's solutions but I don't understand them yet): http://www.phy.syr.edu/courses/PHY212.08spring/HW/WHW-3.pdf Draw vectors at...
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    Hydrophobicity and colorimetry

    Homework Statement Given four compounds that are variations on amines (compound one has -OH funcitonal groups, compound 2 has a carboxy group, etc.). I am also given a bright yellow compound, which will ultimately be covalently linked to each of the four compounds via amide bond (it is a...
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    Find Vector Bisecting Angle Between 3i+4j and 8i-15j

    Thanks Dick. Perhaps I'm missing the point, though-- how would I apply this when my two given vectors are of different magnitudes?
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    Find Vector Bisecting Angle Between 3i+4j and 8i-15j

    Homework Statement Find a vector v that bisects the smaller of the two angles formed by 3i+4j and 8i-15j. Homework Equations dot product: cos(theta)= u*v/(||u|| ||v||) The Attempt at a Solution I first found the angle in question by putting the two given vectors into the...
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    Level Surfaces Problem- Calc III

    To Sammy: Oh, I misunderstood the previous wording. 3x-4y-z=0 So, to "turn this number into the 8 you need," add 8 to both sides? hence f(x,y,z) = 3x-4y-z+8
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    Level Surfaces Problem- Calc III

    ... I would hazard a guess at no. Would it be permissible for you to numerically work though one of either my examples or yours, and we'll see if I can get the subsequent examples from looking at that that? Verbal explanations clearly aren't working (though I appreciate them!). From your...
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