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Homework Help: Which is the area of each faces for the rectangular prism.

  1. Sep 17, 2008 #1
    1. The problem statement, all variables and given/known data

    Considering a rectangular prism bounded by six rectangular faces (x=2, y=0.5,
    z=1) and a cylinder (r=0.5, heigh h=2) that cut the rectangular prism in x=1
    y=0 and z=0 with a inclination of 45 grads in y and z. Which is the area of
    each faces for the rectangular prism. I need not the numerically solutions but
    the analytically solution.

    2. Relevant equations

    3. The attempt at a solution

    The area of each face of a rectangular prism is Ar=a*b but now I must rest the
    area of the cylinder. The cylinder area is known as Ac=2*pi*r*h. But this is
    not the result. If the rectangular prism would be a cube, it would be very
    easy: the area of the rectangle minus the area of the semicircle. But in this
    case I think I have to consider that the cylinder cut the rectangular prism
    with a inclination, but I am not sure.
  2. jcsd
  3. Sep 17, 2008 #2


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    Science Advisor

    Re: geometry

    That's only 3 faces. I would assume the other 3 are x=0, y= 0, z= 0 but you mention x= 1 below. Are the faces x= 1, y= 0, z= 0, x= 2, y= 0.5, z= 1?

    The height is not relevant if the cylinder goes all the way through the prism. But the precise location is. What line is the axis of the cylinder? "45 grads"= [itex]0.45\pi/2[/itex] radians.

    The area of the faces is trivial. Do you mean the area of each face inside the cylinder?

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