A Simple Science Teaser

This theme has been discussed before, but since the answers i have heard so far are not within my perception here's my explanation. All images are projected at each eye's retina inverted both horisontally and vertically. But since brain has to combine the two inverted images AND bind them together to a single picture they must be once again inverted by brain's optical center at one dimension only (vertical) because of human eyes line being 'horizontal'. Mirror reflection "perception" just reveals your brain's "cheating". Beat that. S.M.

Hello, Bravo88,

I'm not a photonics engineer (or any kind of engineer for that matter) so take everything I say with a grain of salt.

But I suspect it's because the reflective surface is simply sending back to the viewer what it 'sees' on a one to one basis. For an inversion to take place, you'd have to have something like a lens between the mirror and the subject, to perform a top-to-bottom 'flip' or inversion of the light rays passing through it.

If I remember my retinologist correctly, this 'flip' takes place inside the human eye, too, because we have a built-in lens. The image seen by the eye is actually inverted on the retina at the rear of the eyeball, but our brains have adapted to that and do a sort of 'counter-inversion' which makes everything look normal. So damage to the lower part of the retina would result in a corresponding vision loss in the upper part of a person's viewing area and vice versa.

But how do we know what is normal?

Maybe we are all actually walking upside down....

Normal is an average collection of abnormalities.

GA

Your explanation makes more sense, except the the eye inversion simply does not matter in the slightest.

If you lie down and look in a mirror, you can then ask why the mirror inverts vertically but not laterally.

The answer is the same in each case...and can for now remain an exercise for the reader.

Correct, and if you had a right hand sticking out the top of your head, it would be a left hand in the mirror.

I plead the phonetic with spooklight.

as for the mirror it doesn't care it sends light on from all directions, when you stand in front what you see on the right is on your right, left is left,up is up down is down but it is us that rotates when we look back thus changing the point of view.

This is an old puzzler. The correct answer is that a mirror actually reverses front to back. Consider a mirror placed north of an object, facing the object; the part of the object closest to the mirror--the northern most part of the object--is the southernmost part of the virtual image in the mirror. Likewise, the southernmost part of the object is the northernmost part of the virtual image in the mirror.

Hi,

When you want to compare two objects and check to what extent they are similar you put them physically side by side, in the same position. Then you go mentally further and imagine superimposing the two objects so they will fuse into one object, so any difference will be highlighted.

Standing in front of a mirror, after some time you may start to compare your image with what you know is your real self.

You will imagine (=picture yourself) walking into the mirror, Alice-style, and standing beside your frozen image, or even letting the image be formed on your body. Then you will realize that your right hand's image corresponds to your left hand and vice-versa, and you will say your image has been inverted horizontally. This is because when you "walk in" you keep an upright position.

Now imagine jumping weightless (it's your imagination) into the mirror and trying the same thing while standing on your hands, your body upside down. Now both left hands will coincide and so on. But you will say there is a vertical inversion.

So there is one inversion in any case. Your tagging it "vertical" or "horizontal" is not given by the physical phenomenon, but by your interpretation.

Fooled again by bilateral symmetry...!

Also what do the people (who live in mirror world) in the mirror call it.....a rorrim?

GA - You have it! The mirror does not turn it around, we do when we look at the image from the opposite direction. Turn it up side down and the image will be up side down also.

Mirror will reflect a direct image of the object in front. Answer will be clear if you mark route of incident rays & reflected rays on paper

A mirror image is NOT an inverted image. It is a replica. That is why writing or printing viewed in a mirror is reversed but not inverted. Think letterpress. Think offset. Think hectograph .

To paint a self portrait one needs two mirrors. That's all I have to know.

Otherwise my glass eye would be on the other side

A mirror reflects light at the same angle magnitude but opposite sign with respect to a normal from the mirror plane. A point in front of the mirror has a virtual image behind the mirror. Each point in the image at a distance y from the mirror has a corresponding virtual point at a distance y behind the mirror.

I find pictures are a good way to understand so The easiest way is to draw a picture on some graph paper with a mirror as the horizontal (x) axis and do some ray tracing. If you draw a point (x=0, y=2) and a corresponding virtual image (x=0 and y=-2) then you can put your 'eye' position at different points and draw the rays. For example, if your eye is at x=2, y=2 then you see the virtual image (join x=2, y=2 to x=0,y=-2) and the ray crosses the mirror at x=1,y=0. The ray from the object (join x=1, y=0 and x=0, y=2) has the same angle with respect to the mirror surface.

You need to separate the concepts of mirror and rotation to understand what you see. If the image is mirrored then the object and reflection will move in the same direction at the same time. If an object is rotated then the points move in opposite directions. Look in a mirror and try it then hook up a video camera to a TV and watch yourself move about (its is great fun with the kids).

Take a few minutes to pop over the Challenge Questions Forum. The questions has been asked and answered there several times.

I wonder if this time will take as long

A mirror does not Invert or reverse, IT Gives what is called a MIRROR IMAGE: Facing the mirror, what is at the left remains at the left and the right remains at the right while the top also remains at the top and the bottom remains at the bottom.

It is an OPPOSITE Image = Mirror Image. Not a puzzle but a trick question only at best!!

Write TEST Horizontally and Vertically on a sheet pf paper and face it to the mirror. if the paper is slightly transparent, put it on the mirror glass and see that everything matches: Left = left, right = right top = top. It is when you try to imagine yourself in the mirror and looking back at yourself that you get confused...

Why do mirror invert laterally but not vertically? Meaning when you look into the mirror,the left become the right, right become left, but the top remains as the top?

The mirror is not really inverting anything. It is only reflecting the image of precisely what is in front of it. Left to right, our image is symmetrically identical. Our bodies are essentially a mirror image of themselves, if we look at the left side & then the right & vice versa. But they are not symmetrically the same top to bottom. Our mental juxtapositioning and superimposition of ourselves onto the reflected image makes it appear that the mirror has inverted us and reversed the left to the right..

Well it isn't really inverting anything, just laterally transposing it; ie, reflection.

"Why do mirror(s) invert laterally but not vertically?"

I think everyone has missed the obvious on this one. If our eyes were aligned vertically rather than horizontally then we would only see things mirrored vertically. What is really happening is that all reflections stay on the same side as before; we merely see things backward because the light is now coming from the opposite direction from which it originated. This is true for top and bottom as well as right and left. Things that are on the right stay on the right, they don't shift to the left. We just associate right and left differently when looking at the mirrored image.