Recent content by NoOne0507

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    Control Systems: How Does High Gain Affect the System?

    I came up with this question while studying for an upcoming exam. I had a design problem, my solution gave me a gain of about 5500 with a PI compensator. Does having that high of a gain screw with my system? It gives me the desired results in MATLAB, but are there any drawbacks to doing that?
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    Graduate Question on assumptions made during variation of parameters

    I was recently trying to prove the variation of parameters formula for an nth degree equation, and I have come up with a question about the assumptions made during the derivation. During the derivation we assume that: u1'y1(k) + u2'y2(k) + . . . + un'yn(k) = 0 for k < n-1. It leads to the...
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    What is the pre‐exponential coefficient for this reaction?

    Homework Statement I have two problems with this: 1) I am not sure if I am using the right constant. 2) I have no idea if my values are realistic. The actual question: The rate of a reaction is 25.00 units per time at 20.00°C. The activation energy barrier for this reaction is 1.50 eV. a)...
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    Finding the total power delivered

    That makes sense. It struck me as odd that that was the way to solve it, but it was asking for power, and I couldn't figure out any other way to get a unit of power. Thanks.
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    Finding the total power delivered

    Well this is the full question: The voltage v is a constant 10 volts and the current i is described by the following function: i(t) = (5t^2+20+6)/(t^3+2t^2+t) Amps What is the total power delivered between t=1s and t=5s? I figured since P is a function of time it would work since ∫ dP = ∫...
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    Finding the total power delivered

    I'm really only concerned with the setup so I'm just going to ask it in a general sense, rather than the specific problem. Homework Statement Suppose you have a constant voltage and the current is described by i(t). Find the total power delivered between time A and time B. Homework...
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    Undergrad Is a vector in a vectorspace its own projection onto that vectorspace?

    If V is a vectorspace and v is a vector in V. will the projection of v onto V be v?
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    High School Why does my calculator compute ln(5) faster than ln(e)?

    Straightforward question for anyone who knows how calculators work.
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    Lagrange Multipliers. All variables cancel

    T(x,y,z)=60(y^2 + z^2 - x^2) T(0,0,0) = 0 T(1,0,0) = -60 T(-1,0,0) = -60 T(0,y,z) = 60(y^2+z^2), but since this is along a circle T(0,y,z) = 60 Which gives the minimum at (1,0,0) and (-1,0,0), and the max at (0,y,z) where y^2+z^2=1. Okay, so from (almost) the beginning: λ = -60, x≠0...
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    Lagrange Multipliers. All variables cancel

    Well if x=0 then the constraint becomes y^2+z^2=1, with λ=60. So would the maxima occur anywhere in the yz unit circle? Which would yield (0, y, ±√(1-y^2)) as the maxima? And then the smallest λ would occur at x≠0, and y=z=0? Which would give Minima on x: [-1,0) U (0,1] y=0 z=0 Or am...
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    Lagrange Multipliers. All variables cancel

    But couldn't x be any value? For x ≠ 0, λ=-60. And then when x = 0 we get 0=0 with no λ. If you do that for all the values you can get x=y=z=0, plug into the constraint and get the center of the circle, with no value for λ. How would that help find the max and the min?
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    Lagrange Multipliers. All variables cancel

    Homework Statement A cannonball is heated with with temperature distribution T(x,y,z)=60(y2+z2-x2). The cannonball is a sphere of 1 ft with it's center at the origin a) Where are the max and min temperatures in the cannonball, and where do they occur?Homework Equations \nablaf=λ\nablag Where...
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    Undergrad Derivative of arcsec(x) and arccsc(x)

    I was trying to prove the derivatives of the inverse trig functions, but I ran into a problem when I tried doing it with arcsecant and arccosecant. So the general process is this: y = arcsec(x) sec(y) = x dy/dx * sec(y)tan(y) = 1 dy/dx = 1/[sex(y)tan(y)] sec(y) = x And for tan(y) we...
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    Integrating Tangent by parts; 0 = -1

    Homework Statement The question is what has gone wrong in this proof, it is worth noting this a definite integral between pi/6 and pi/4: ∫ tan(x) dx = ∫ sin(x)/cos(x) dx Let u = 1/cos(x) and dv = sin(x) dx So du= sec(x)tan(x) and v = -cos(x) When we substitute back in we get: ∫ tan(x)...