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Mirror, Mirror on the Wall (November '22 Challenge Question)

Posted October 31, 2022 12:00 AM
Pathfinder Tags: challenge question

Why do mirrors reverse left and right, but not up and down?

Image credit: Ryan Somma/CC BY 2.0

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#1

Re: Mirror, Mirror on the Wall (November '22 Challenge Question)

10/31/2022 2:14 AM

Because the mirror is a reflection, not an alternate viewing angle...

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#6
In reply to #1

Re: Mirror, Mirror on the Wall (November '22 Challenge Question)

11/01/2022 12:12 AM

A mirror is a reflection and an alternate viewing position.

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#2

Re: Mirror, Mirror on the Wall (November '22 Challenge Question)

10/31/2022 3:54 AM

In fact, they don't reverse left to right either: think about it, the image of your right hand is still to your right.

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#7
In reply to #2

Re: Mirror, Mirror on the Wall (November '22 Challenge Question)

11/01/2022 12:22 AM

They do in fact reverse the image. Look in a mirror. Your wedding ring, if you have one, is on in the image's right hand instead of the traditional left hand. If you wiggle your right hand, it looks like the image is wiggling its left hand.

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#11
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Re: Mirror, Mirror on the Wall (November '22 Challenge Question)

11/01/2022 5:55 AM

"Your wedding ring, if you have one, is on in the image's right hand"

Because the mirror has not reversed left to right.

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#16
In reply to #11

Re: Mirror, Mirror on the Wall (November '22 Challenge Question)

11/01/2022 8:14 PM

"Because the mirror has not reversed left to right."

Yes it has. If your body double stood in front and faced you so as to replace the mirror, his wedding ring would still be on his left hand. The mirrow image showed the ring on the image's right hand. That means reversal for me.

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#23
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Re: Mirror, Mirror on the Wall (November '22 Challenge Question)

11/02/2022 5:03 AM

Perhaps, if I said: Because the mirror has not reversed left to right, in the same way as it does not reverse up to down.

Think about this: if you lay on your side, and, looked in a mirror; would you then believe that the mirror was reversing up to down, and not, reversing left to right?

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#13
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Re: Mirror, Mirror on the Wall (November '22 Challenge Question)

11/01/2022 10:29 AM

But the image of the right hand is the image's left hand. See what I wrote about the wedding ring below.

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#26
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Re: Mirror, Mirror on the Wall (November '22 Challenge Question)

11/03/2022 6:41 AM

How you see yourself in the mirror..a reflection......How other people see you...an alternate viewing location

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#3

Re: Mirror, Mirror on the Wall (November '22 Challenge Question)

10/31/2022 7:43 AM

Why do mirrors reverse left and right, but not up and down?

They neither reverse left/right nor up/down. They reverse front/back, the axis perpendicular to the plane of the mirror.

If you are facing north looking in a mirror, your left hand is west as is your reflection's, your head is up as is your reflection's, but your reflection's front is facing south.

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#8
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Re: Mirror, Mirror on the Wall (November '22 Challenge Question)

11/01/2022 12:26 AM

They reverse left/right, but not up/down. I will explain why below.

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#20
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Re: Mirror, Mirror on the Wall (November '22 Challenge Question)

11/02/2022 12:28 AM

When we look at ourselves in the mirror the right hand is still on the right side of our body. The reflected image is backwards (front/back)

Because we look at letters from left to right, writing in a mirror is reversed . The letter sequence of words and sentences are viewed, left to right. The symmetrical letters, i l o v w x, would look the same viewed in a mirror but other letters a b c etc. look different when viewed in the mirror The proper noun OXO is the only word I know that can be viewed from either side to look the same.

The prior recognition in our mind of the letters and words is one of the things that makes them difficult to instantly know or understand when viewed backwards

Writing behind office glass door backwards

Writing in Mirror behind office glass door around the right way

Writing in front of office glass door

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#25
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Re: Mirror, Mirror on the Wall (November '22 Challenge Question)

11/02/2022 10:44 AM

"When we look at ourselves in the mirror the right hand is still on the right side of our body. The reflected image is

backwards (front/back)"

When you look at yourself in a mirror, anything in your right hand will appear in your image's

left hand. The reflected image is reversed.

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#27
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Re: Mirror, Mirror on the Wall (November '22 Challenge Question)

11/15/2022 9:17 AM

This is actually the correct answer. It even has easily understandable illustrations. Unfortunately, people cannot get past the letters being backwards on their tee-shirts'.

As is often the case, true understanding takes a back seat to subjective observation.

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#28
In reply to #3

Re: Mirror, Mirror on the Wall (November '22 Challenge Question)

11/21/2022 11:05 AM

This is the first answer that begins to speak to the answer. Mirrors don't reverse left and right, nor up and down. The reflect front/back, which could also be though of as in/out, thanks to specular reflection.

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#4

Re: Mirror, Mirror on the Wall (November '22 Challenge Question)

10/31/2022 6:56 PM

A mirror displays what another person would see from outside of your body.Look at selfies.

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#5
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Re: Mirror, Mirror on the Wall (November '22 Challenge Question)

10/31/2022 11:27 PM

No....

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#9
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Re: Mirror, Mirror on the Wall (November '22 Challenge Question)

11/01/2022 12:43 AM

Au contraire, if a person in a lettered sweatshirt stands in front of to a mirror, the letters would appear backwards. However, another person would see the shirt lettering as it really is. A mirror image is not the same as a photographic image.

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#10

Re: Mirror, Mirror on the Wall (November '22 Challenge Question)

11/01/2022 1:13 AM

OK, so why does a mirror reverse and not invert? Suppose a portrait is standing vertically on a table and facing the observer. A mirror image of the portrait would look like the portrait was turned 180° while keeping the bottom on the table and viewed from the back, assuming the back was transparent. From the back, right would be left and vise versa, just like a mirror. The top and bottom would not reverse because they were not interchanged during the above rotation. So a mirror reflects back an image comparable to looking at something from behind with x-ray eys.

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#12

Re: Mirror, Mirror on the Wall (November '22 Challenge Question)

11/01/2022 9:26 AM

They do not. Your left shoulder is on the left side of the mirror. The mirror reflects exactly what it "sees." It is YOU that is turned left to right presenting yourself to the mirror.

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#14
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Re: Mirror, Mirror on the Wall (November '22 Challenge Question)

11/01/2022 10:39 AM

If a parrot were sitting on your left shoulder, the image would show the parrot sitting on the image's right shoulder. Of course the image's right shoulder would appear to the left because the image is facing you.

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#15

Re: Mirror, Mirror on the Wall (November '22 Challenge Question)

11/01/2022 3:57 PM

We’ll leave that up to the eye ball…

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#17
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Re: Mirror, Mirror on the Wall (November '22 Challenge Question)

11/01/2022 8:24 PM

"We’ll leave that up to the eye ball…"

Not quite. The brain is also in the presentation chain of the image. It displays an image orientation the same as an upright image taken with a common camera.

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#18
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Re: Mirror, Mirror on the Wall (November '22 Challenge Question)

11/01/2022 8:54 PM

keep brains out of it. That’s why we leave it ‘just’ up to the eye ball.

And if you keep brains out of it… you’d have a career politician. Which explains a lot….

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#19
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Re: Mirror, Mirror on the Wall (November '22 Challenge Question)

11/01/2022 9:31 PM

keep brains out of it. That’s why we leave it ‘just’ up to the eye ball.

And if you keep brains out of it… you’d have a career politician. Which explains a lot….

You cannot disregard the role the brain plays in the interprtation of the image. It takes the upside-down image from the back of the retina and presents it upright to the viewer.

Most career politicians, Biden is an exception, are pretty smart. But, they are smart in a cunning way. That is, they use their exceptional intelligence to further their own goals and desires instead of doing what is best for the citizens that voted for them.

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#22
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Re: Mirror, Mirror on the Wall (November '22 Challenge Question)

11/02/2022 3:51 AM

they are smart in a cunning way.

like a virus.

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#21

Re: Mirror, Mirror on the Wall (November '22 Challenge Question)

11/02/2022 2:49 AM

Actually, a concave mirror revers up and down!

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#24

Re: Mirror, Mirror on the Wall (November '22 Challenge Question)

11/02/2022 6:37 AM

The statement is not entirely true if you lay on your side. the mirror would give a reflection "reverse" left and right of your body, in the up and down,

If you are lying on your side is the room reversed back to front.

Up is still up if you are standing up, and point in any direction but left and right are relative to your body direction

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