• bleistift2@sopuli.xyz
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    28 days ago

    If you’d be so kind, how far do you have to get away from a flat mirror to show your whole image?

    • unexposedhazard@discuss.tchncs.de
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      28 days ago

      Depends on the size of the mirror and how far it is off the ground. If its a full sized 2m tall mirror then the min distance is obviously zero. If its a small bathroom sink mirror that doesnt go down to the floor, then you need to be really far away, further than you can be in a bathroom.

      • Tar_Alcaran@sh.itjust.works
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        28 days ago

        Uhhh no, that’s not how angles work.

        The further you get away from a mirror, the “further away” the reflection is. You will never see your whole body in a hand mirror, even if you put it on the moon.

        • candybrie@lemmy.world
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          28 days ago

          The reflection being further is the point? The further away something is, the smaller it looks, so the less of your field of view it takes up, the more you can see of it.

          If I put my hand on my eye, I can’t see much of it. If I pull my hand back, I can see more of it. If I put a mirror on my eye, I can only see my eye. If I put it back, I can see my face because the reflection of my face is further (i.e. smaller).

          I’m very confused what you’re trying to say.

          • Tar_Alcaran@sh.itjust.works
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            28 days ago

            Ok, visualize it like this:

            Draw yourself, with a small mirror at head height, a meter away. Draw your reflection at the same distance from the mirror on the other side.

            Now do that again, but place the mirror 10 times further. Then draw lines from your eye, to the edge of the mirror, and to the reflection.

            You’ll reach the same point on your reflection.

            Edit: or let the BBC do it for you; https://www.bbc.co.uk/bang/images/dallas_mirror_diagram_large.gif

            • candybrie@lemmy.world
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              27 days ago

              Ok, I can see the point, but it’s not usually what people mean when they can see their whole body. In that example, you’re looking down or looking up. You never see your whole body at the same time. For your whole body to be entirely in your field of view, it absolutely does matter how close or far you are from the mirror. You can test it by going closer and further to any mirror.

              • Tar_Alcaran@sh.itjust.works
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                27 days ago

                … buddy, have you tried it? Get up, walk to a mirror and test it. You’ll find that the picture shows you what happens

                • candybrie@lemmy.world
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                  26 days ago

                  Yes, I have.

                  Have you tried it? Find a mirror big enough to show your whole body and press your face right up to it. Do you see your whole body? Now take a step back, do you see your whole body at the same time without having to look and up and down? Now walk several steps back and notice how much more you can see without moving your eyes.

                  We’re talking about 2 separate concepts is the problem.

                  • Tar_Alcaran@sh.itjust.works
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                    26 days ago

                    Ok, so, your point is that eyes have a limited field of view? Yeah, that’s something totally different, and not at all what this was about.