B Scattering of light by dust particles

AI Thread Summary
Light scattering by dust particles is visible in a dark room when light enters through a small opening, making the particles appear as bright dots. In contrast, when a window is fully open, the increased background brightness makes it difficult to see the scattered light from the dust. This phenomenon is similar to observing stars, which are only visible at night due to the darkness, although some celestial bodies like Venus and the Moon can occasionally be seen during the day. The visibility of scattered light is thus heavily influenced by the surrounding light conditions. Understanding this principle highlights the interplay between light, visibility, and background brightness.
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Inside a dark room, when light comes through a hole, we see the dust particles as the particles scatter the light. But, when the whole window is open, we don't see the dust particles scattering the light. Why?
Inside a dark room, when light comes through a hole, we see the dust particles as the particles scatter the light. But, when the whole window is open, we don't see the dust particles scattering the light. Why?
 
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Because when the whole window is available the background is also bright and small bright dots are hard to see against a bright background.
 
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Pushoam said:
when the whole window is open, we don't see the dust particles scattering the light.
I have seen dust particles scattering light many times in a room with an open window.
 
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Its the same reason you can see stars (and planets) only at night, although sometimes one can see Venus and or the Moon in the daylight (to which @Dale alludes above.
 
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Thanks to all.
 
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