Surface area of inclined XY plane at 45 degrees

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The discussion focuses on calculating the surface area of a square rotated 45 degrees around the z-axis, transforming it into a rectangle. The original square has an area of a^2, while the new area involves a base of a and a reduced height h, leading to the equation Area = a * h. Participants suggest using coordinates and a rotation matrix to analytically determine the new dimensions and area. The conversation also touches on the implications for crop growth and insolation on the altered surface. The key question remains whether the area can be simplified to just sqrt(2) or if a more complex calculation is necessary.
marciokoko
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Homework Statement
A regular 2 dimensional square has a surface area b*h. But if we rotate the plane on a z axis by 45 degrees (and are forced to extend the length of let’s say, the base, then I guess what happens is that the square now becomes a rectangle with longer sides for b.

Is there a way to calculate how much longer the sides got given the plane must still reside within the original square dimensions?

I’m trying to find out how much more surface area you get by growing crops on a flat square versus that now elongated rectangle obtained by rotating the original square 45 degrees on that z axis.

Not sure if I’m being clear enough. Lemme know.
Relevant Equations
Base x height and possibly 1:1:sqrt 2
Is it just sqrt2?
 
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marciokoko said:
Homework Statement: A regular 2 dimensional square has a surface area b*h. But if we rotate the plane on a z axis by 45 degrees (and are forced to extend the length of let’s say, the base, then I guess what happens is that the square now becomes a rectangle with longer sides for b.

Is there a way to calculate how much longer the sides got given the plane must still reside within the original square dimensions?

I’m trying to find out how much more surface area you get by growing crops on a flat square versus that now elongated rectangle obtained by rotating the original square 45 degrees on that z axis.

Not sure if I’m being clear enough. Lemme know.
Relevant Equations: Base x height and possibly 1:1:sqrt 2

Is it just sqrt2?
Are you familiar with the Pythagorean theorem and the definition of the sine of an angle?
 
Square_Edge_view.png
When you look at the square of side ##a## before you rotate it, you see an area equal to the base times the height, ##Area=a\times a =a^2##. When you rotate about the base, the base is still ##a##, but the height gets shorter, call it ##h##. The new area is ##Area = a\times h## (see figure on the right.)

Can you find the relation between ##a## and #h##? See @Chestermiller's post.
 
marciokoko said:
Homework Statement: A regular 2 dimensional square has a surface area b*h. But if we rotate the plane on a z axis by 45 degrees (and are forced to extend the length of let’s say, the base, then I guess what happens is that the square now becomes a rectangle with longer sides for b.

Is there a way to calculate how much longer the sides got given the plane must still reside within the original square dimensions?

I’m trying to find out how much more surface area you get by growing crops on a flat square versus that now elongated rectangle obtained by rotating the original square 45 degrees on that z axis.

Not sure if I’m being clear enough. Lemme know.
Relevant Equations: Base x height and possibly 1:1:sqrt 2

Is it just sqrt2?
You may be able to do this analytically by using coordinates, with your square having vertex set {##(0,0), (0,a), (a,0), (a,a)##}, then applying a rotation matrix to the vertices, then extending. You'll end up with a figure made of rectangles and triangles who's area you can easily find, or, you may easily integrate some simple linear maps.
 
marciokoko said:
how much more surface area you get by growing crops on a flat square versus that now elongated rectangle obtained by rotating the original square 45 degrees on that z axis.
What about insolation?
 
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