Looking in a small mirror, do you actually see a larger portion of your face when you hold the mirror farther away?
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Problem
Looking in a small mirror, do you actually see a larger portion of your face when you hold the mirror farther away? (You are allowed to use experiment as well as reasoning...) -- Daniel P. B. Smith <dpbsmith@world.std.com>
Show solution
In article <4r3pbn$kb3@wanda.phl.pond.com>, Matthew T. Russotto <russotto@wanda.phl.pond.com> writes: > With a flat mirror, you see the same portion of your face when you > hold the mirror further away. In fact, if the mirror is 3" by 5", you > will see 3" x 5" of your face. Make that 6" x 10" of your face. The virtual position of the face-image is twice as far from you as the mirror is. I recommend testing this with a CD. It's shiny, and it's pretty close to half the size of my face. So the image of my face fits very neatly within it. -- Andrew C. Plotkin <erkyrath+@CMU.EDU> ---- A 3" x 5" mirror should let you see about 9" x 10" of your face. Each eye will get a 6" x 10" view, and if your eyes are about 3" apart, each will see a 3" wide strip the other eye doesn't see. And you do see more when you hold it farther away. But only a little bit. It's because your face curves away from the mirror, so if you hold it too close the bits around the edges are blocked. Try holding a mirror of any size right up to your nose. You can't see your ears any more. -- Paul Filseth <pgf@lsil.com>