Recent content by cos(e)

  1. C

    Normal to parameterised surface

    the points are u=0 and v=-2, so is the tangent plane is Tu(0,2)*(u-0)+Tv(0,2)*(v-2)=0
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    Normal to parameterised surface

    ok got the first part thanks, now for the area, i know in the double integral has |J| in it somehow, how wuld i find it. I know from a mate u can do |Tu X Tv|, but i don't think we learned this, and i was wondering how wuld u do this by using jacobians, if possible. im confused coz we...
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    Normal to parameterised surface

    cross product
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    Normal to parameterised surface

    Homework Statement surface : $(u,v) is (e^u,(v^2)*(e^(2u)),2e^(-u) +v) 0<=u<=3 -4<=v<=4 find a normal in terms of u and v write down a double integral for the surface(dont solve) find equation of tangent plane to surface at (1,4,0) Homework Equations The Attempt at a Solution...
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    Double Integral: Change of Variables for dx/(x+y) = 3

    ok i forgot bout the jacobian so i tried J= |delx/delu delx/delv | |dely/delu dely/delv | and i got J=u, which gives the right answer, yet I am not sure if I am doing this right i feel i fluked the answer
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    Double Integral: Change of Variables for dx/(x+y) = 3

    Homework Statement Let D be the region bounded by x=0, y=0, x+y=1, x+y=4. Using the change on variables x=u-uv, y=uv and the jacobian, evaluate the double integral double integral of dxdy/(x+y) Homework Equations answer is 3The Attempt at a Solution i drew the graph and found the...
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    Solving Basic Stokes Theorem Homework on Ellipse

    thanks, its just isn't the normal grad(g), or am i getting this confused with somethig else?
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    Solving Basic Stokes Theorem Homework on Ellipse

    Homework Statement Use the surface integral in stokes theorem to find circulation of field F around the curve C. F=x^2i+2xj+z^2k C: the ellipse 4x^2+y^2=4 in the xy plane, counterclockwise when viewed from above Homework Equations stokes theroem: cirlulation=double integral of nabla...
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    Calculating Surface Area Using Parametrization: Tilted Plane Inside Cylinder

    thanks :)
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    Calculating Surface Area Using Parametrization: Tilted Plane Inside Cylinder

    Homework Statement Use parametrization to express the area of the surface as a double integral. tilted plane inside cylinder, the portion of the plane y+2z=2 inside the cylinder x^2+y^2=1 Homework Equations the area of a smooth surface r(u,v)=f(u,v)i+g(u,v)j+h(u,v)k a<=u<=b...
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    Undergrad Max Efficiency of a Carnot Engine vs Other Engines

    thanks
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    Undergrad Max Efficiency of a Carnot Engine vs Other Engines

    quick question, is the difference between a carnot engine to an engine is that the engines eff is less than or equal 1-(cold temp / hot temp), and the carnot is the max of this which is just equal 1-(cold temp / hot temp)?
    • cos(e)
    • Thread
    • Carnot Carnot engine Efficiency Engine Engines Max
    • Replies: 2
    • Forum: Thermodynamics
  13. C

    This is the same result as the back of the book. So your solution is correct.

    ok i get the answer with p=k(hat) now I am sure why I am letting p=k(hat), is it because p is the normal to the area of the double intergral i take, in this case the x-y plane with theta varying from 0 to pi/2 adn r varying from 0 to a?
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    This is the same result as the back of the book. So your solution is correct.

    Homework Statement find the flux of the field F(vector) across the portion of the sphere x^2+y^2+z^2=a^2 in the first octant directed away from the origin Homework Equations F(x,y,z)=zk(hat) The Attempt at a Solution i used Flux=double integral over x-y plane F.n(unit...
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    Graduate Process such as isobaric, isochoric, quasistatic, adiabatic

    do we use delta H= n*Cp* delta T even when the pressure is not constant? What do u mean by reversible process, i havnt learned that yet :S