Optical illusions are FUN! - Democratic Underground

Endangered Specie

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Fri Nov-05-04 10:48 PM
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Optical illusions are FUN!

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MadAsHellNewYorker

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Fri Nov-05-04 10:57 PM
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1. has someone been getting into the acid again?

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starroute

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Fri Nov-05-04 11:02 PM
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2. Go here

http://www.ritsumei.ac.jp/~akitaoka/index-e.html

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MadAsHellNewYorker

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Fri Nov-05-04 11:04 PM
Response to Reply #2

3. looks like i need to get into that acid again....

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HysteryDiagnosis

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Fri Nov-05-04 11:07 PM
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4. Oh.... so you like that.... have at it..... no need to move your head....

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HysteryDiagnosis

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Fri Nov-05-04 11:09 PM
Response to Reply #4

5. And then you can tell me where the missing piece is.... maybe.....

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WannaJumpMyScooter

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Fri Nov-05-04 11:12 PM
Response to Reply #5

7. Actually that one is not too tough

Simple. It is the difference in horizontal length between the red and green triangles which moves the brown piece in and out.

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Endangered Specie

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Fri Nov-05-04 11:42 PM
Response to Reply #5

9. Although it appears so...

the slopes of the red and dark green triangles are different (but only slightly, so that you dont notice unless you actually figure the slope=rise/run ratios). Strictly speaking those two images are not triangles since the hypoteneuse is not a straight line.... thats the key to it.

There is no missing piece, it just so happens that the pieces selected form what look like two 'equal' sized triangles, when in fact they are not the same.

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WannaJumpMyScooter

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Sat Nov-06-04 08:16 PM
Response to Reply #9

12. Nice theory, but... they are right triangles... check them out

the run and rise is correct, the only difference is in the run of the two, and that makes the hole.

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petronius

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Sat Nov-06-04 09:19 PM
Response to Reply #12

13. The two triangles are not exactly congruent,

and the figure is not drawn exactly the same in the top and bottom.

To see this, start at the far left vertex and count 5 over and two up (the size of the green triangle) in both figures - notice how the hypotenuse is in a slightly different place? The trick is that the lines are thick enough that you assume the hypotenuse is pasing right through the grid intersections, when it really isn't...

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WannaJumpMyScooter

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Sat Nov-06-04 09:47 PM
Response to Reply #13

14. Possibly, but that does not explain the gap.

The only expliantion for the gap is, as I said above, the difference in horizontal run of the two triangles.

I have taken it apart in photoshop... all the pieces are the same size in both pictures.

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petronius

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Sat Nov-06-04 11:43 PM
Response to Reply #14

16. Right, the pieces are the same in both figures

but the hypotenuse of the overall triangle is not a straight line because the two sub-triangles (red and green) are not the same shape. The small (left side) vertex of the red triangle is a slightly smaller angle than the corresponding vertex in the green triangle, by about half a degree. This means that the hypotenuse of the total triangle is bent a tiny bit inward in the top figure and a bit outward in the bottom figure. This bend in the overall hypotenuse occurs where the two sub-triangles meet. The resulting difference in area adds up to the extra square.

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pdx_prog

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Sat Nov-06-04 10:01 PM
Response to Reply #4

15. I just flashed back to 1976...

one late sat night....his shag carpet was laying down in different directions.....the curtains were moving, and the recliner was breathing. One guy was talking to me....he had an unruly, wild and uncombed afro that was moving like the medusa's....his hair had a mind of it's own and I was totally wasted....

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Ready4Change

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Fri Nov-05-04 11:09 PM
Response to Original message

6. The best part of that illusion?

Show it to someone else, then imagine chicken noises as they make it work.

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HysteryDiagnosis

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Fri Nov-05-04 11:14 PM
Response to Reply #6

8. Ahhhhhhhh!!!!! Too funny!!! n/t

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underseasurveyor

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Sat Nov-06-04 12:48 AM
Response to Original message

10. I also like these kinds of hide n seek pictures

The art work of Bev Doolittle.

https://www.artifactsgallery.com/art.asp?!=A&ID=612

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MisterP

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Sat Nov-06-04 01:02 AM
Response to Original message

11. I'm immune to a lot of them: it's like going in & out of focus for me

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