Why is stuff “far away” in the mirror blurry for me (im short sighted), even though the mirror is right in front of me?
In: Physics
mirrors arent screens. They are mirrors. They reflect light, they dont reproduce what they “see”. This is why you dont always see exactly what the mirror is pointed at, but you see what you look at in the mirror. It also means distance is still the same, and lasers still work, and a whole bunch of things.
If you just think of a mirror as a window to behind you, its basically right. No one asks “why is stuff blurry though a window even though the window is close”, but its basically the same question.
That light coming off the mirror started far away, the bounce off the mirror dosnt count.
This is extra text so the bot doesn’t delete my answer. It’s utterly stupid that you’re not allowed to answer an eli5 with a simple response. You’re meant to skip the specifics and give a general understanding.
The object you’re looking at is still just as far away.
The mirror doesn’t re-focus the light, it just passes it along exactly as-is.
So the light hitting your eye ends up being identical in both cases.
The thing that determines if something is blurry for you or not is the focal length which is based on the distance the light travels from the thing to your eyes.
If you were looking at a picture that was a foot in front of you, the light is only travelling a foot.
But if you are looking at a mirror and seeing the reflection of something that is 50 feet behind you, the light of the thing is actually travelling 52 feet to get into your eyes. (50 ft to get to where you are, another foot to get to the mirror and then another foot to get from the mirror back to your eyes).
So now you can see (pun intended) that the focal length is much larger for the object in the mirror compared to the picture.
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