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Why can a lace curtain be seen through by day from inside but not from outside?
There are two causes for that.
One is because of the difference in luminosity, outside being brighter than inside.
The second cause is the keyhole effect. When you look from inside to outside, you are closer to the curtain and you can see more. When you look from outside the distance from you to the curtain is greater and you cannot see very clear.
The two effects combined give you more privacy.
The whiteness of the lace reflects the sunlight and causes pupils to contract to keep too much glare out of your eyes and this makes it difficult to see through the tiny dark openings in the lace. The reverse is true at night. It is easy to see inside while it is nearly impossible to see the anything in the dark outside.
The curtain does not reflect enough light from its inner side to interfere with the much stronger light reflected from objects out of doors. On the other hand, its outer surface is much more strongly lit than things inside the room, and the light reflected from it overcomes the light reflected from them.
by The Examiner-14 years ago
Why do bugs come inside? Why can they not stay outside?The pests are invading my home and I am getting tired of trying to get rid of them the natural way. They do not get the message but keep returning.
by stanwshura5 years ago
How is a pure & absolutely black substance, pigment or object made? Is "true" black even possible??Lots of folks say that black is the combination of all the colors. Well, maybe not lots, but...
by Ayesha Faiz5 years ago
What makes a woman BEAUTIFUL?i think its a beautiful heart that makes a person beautiful!
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