Recent content by njoysci

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    Please help - Gr. 11 physics question about net force calculation

    yes the 360 N for part b) is correct. Drawing the free body diagrams helps keep the signs of the terms correct. For the elevator the forces are (assuming up is positive) cable tension up (positive), weight of elevator + passengers down (negative), and friction force on elevator down (negative)...
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    What Diameter is Needed for the Tube in this Thermodynamics Problem?

    it won't make any difference on gage or absolute
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    Induction Motor Speed: Electrical vs Mechanical

    Refer to the following explanations: ("electrical speed" means electrical AC frequency) https://www.emetor.com/glossary/mechanical-speed/ http://en.wikipedia.org/wiki/Induction_motor
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    Refrigeration theory: Why does the compression follow an isentrope?

    The following explains it nicely: http://www.learnthermo.com/T1-tutorial/ch10/lesson-B/pg04.php
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    How Do Magnetic Field Lines Behave Around a Long Current-Carrying Wire?

    refer to example problem 31.14 for the derivation http://teacher.pas.rochester.edu/phy122/Lecture_Notes/Chapter31/chapter31.html
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    Differences Between Different Thermo Classes

    I've taken all the courses you mentioned (changed major many times trying to decide on a career). You need to check with your university on course prerequisites and corequisites. Generally Physical Chemistry only requires basic chemistry semesters (2 or 3 classes). Mechanical Engineering Thermo...
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    Sampling low pass filtered white noise

    The following summary addresses your questions: http://www.eas.uccs.edu/wickert/ece5650/lectures/N5650_4.pdf
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    Determination of the equation of isentropic processes

    refer to the analysis further down the article http://en.wikipedia.org/wiki/Internal_energy
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    What am I doing wrong when solving this Green's theorem problem?

    Everything is fine except going from second to last step from your answer to the following step. Integral should be of (- (sint)^3 + sint + (cost)^2) dt This will give you the correct answer.
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    Solving Griffiths' Electrodynamics Ex. 10.2

    In this problem we are to derive the electric and magnetic fields at any point P away from an infinite straight wire carrying a constant current I0. Generally, E = -∇V - ∂A/∂t and B = ∇ x A Since the wire has equal positive and negative charges, V = 0 everywhere outside the wire. Once we...
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    Fluid mechanics navier stokes flow around geometry

    Take a look at this site: http://www.math.nyu.edu/faculty/childres/chpseven.PDF
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    Discretion and harmonic amplitude

    your excel spreadsheet is incorrect you should be calculating a DFT (which is the harmonic amplitude) for each k value per the formula they told you to use the α,β values were used to determine the applicable k values they wanted you to use evidentally (which i am very skeptical of initially...
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    Discretion and harmonic amplitude

    The following summary addresses how: http://www.fpv.umb.sk/kat/kf/Integrovana_prirodoveda/TG/Zvuk/Zvuk_kmitanie/www.me.psu.edu/me82/Learning/FFT/FFT.html
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    Why Isn't dv/dy Zero in Stoke's First Problem?

    Your intuition and majority of statements are accurate, just a little variable terminology confusion: U = u i + v j + w k For your example: 0<= u <= V where V = wall velocity; v = 0; w = 0 Therefore ∂v/∂x = ∂v/∂y = ∂v/∂z = 0 and ∂w/∂x = ∂w/∂y = ∂w/∂z = 0 ∇ dot U = ∂u/∂x + ∂v/∂y + ∂w/∂z = 0...
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