Recent content by Learner123

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    Homework about a simple inverting amplifier

    Homework Statement The picture is an closed loop amplifier, the question is simple: find the closed-loop voltage amplifier of the circuit Homework Equations Av = v0/v in = - (R2/R1) The Attempt at a Solution If R2 is just simply a bunch of resistors connecting crazily, then...
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    Help me with Surface intergral!

    the problem is given exactly above, nothin say about first obtant (i also thought about 1st obtant, too when i read the word "portion of", but it seems not that) so i guess the intergral is infinite is right, maybe the instructor gave the wrong problem. I wasn't sure so i asked, thank you for...
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    Help me with Surface intergral!

    Homework Statement Evaluate \int\int (x^2 +4y + z)dS where S is the portion of the plane 3y +2z = 6 with 0<x<3 Homework Equations choosing x, y as variables dS = \sqrt{}(partial dz/dx)^2 + (partial dz/dy)^2 +1 The Attempt at a Solution If i choose x, y as variables or x, z as variables...
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    Intergral problem! !

    got it! i didn't know that after spending 3 calculus classes, what a shame of me! thank you so much for your help and your time.
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    Intergral problem! !

    I tried to do part and this is how i done (for the first intergral): u = x, du = dx, v = 1/2e^(2x), dv = e^(2x)dx uv - \int vdu 1/2xe^(2x) - \int 1/2e^(2x)dx 1/2xe^(2x) - 1/4(e^2 -1 ) x runs from 0 to 1, but 1/2xe^(2x) is not in the intergral part, so how to eliminate x? very...
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    Intergral problem! !

    the first one xe^(2x) thing i guess it's intergral by part, but not sure
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    Intergral problem! !

    Intergral problem! plz help! Homework Statement \oint(x: 0 to 1)\oint(y: \sqrt{}(1 - x^2) to e\overline{}x) xydydx The region bounded by y = e\overline{}x, y = \sqrt{}(1 - x^2), and x =1 3. The Attempt at a Solution i got stuck when i came to the part: 1/2 \oint(x: 0 to 1)...
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    What is speed of o-ray and e-ray and how to obtained?

    i mean the formula to calculate it, any formula with any values (such as wavelength, h, c, m, T, f.....).
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    What is speed of o-ray and e-ray and how to obtained?

    what is speed of o-ray and e-ray and how to obtained?? Homework Statement that's all for the questions. How do i calculate speed of o-ray and e-ray (for example, e-ray and o-ray of calcite) thank you Homework Equations none The Attempt at a Solution surfing web and reading book
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    What is resistance of a DC circuit has resistor n capacitor connect parallel

    what about time constant T = RC, will it be zero also?
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    What is resistance of a DC circuit has resistor n capacitor connect parallel

    does that mean the current won't go through capcitor branch? and that means if i want to find resistance of the circuit, it's simply R?(nothin to do with C) and wat about time constant? T = RC? will it be the same like when capacitor n resistor connect series?
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    What is resistance of a DC circuit has resistor n capacitor connect parallel

    Homework Statement the title says everything, any formula that to find resistance in a DC circuit of one resistor and one capacitor connect parallel, as well as the current through each of R and C (the known values are R C and V) Homework Equations seem to me i = (V/R)e^ (-e/RC), but...
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    Pros help me with physics hw

    the attachment is pending, so no one could open it (i just realized), so i am go ahead host it on imageshack and post the link here, hope everyone would help me http://img519.imageshack.us/my.php?image=85119635si7.jpg
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    Pros help me with physics hw

    Homework Statement hello everybody, i had hw prob due tommorrow, but i couldn't solve, the attached file is the image of the problem (it absolutely has no virus). all known values are labeled in the picture (V, R (same for all), C1 and C2). The questions are: find curren I, and time...
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