How far away are rainbows?
[ 2006-06-05 09:11 ]
People have been asking questions about rainbows since the beginning of time. One question frequently asked is, how far away is a rainbow? That is a tough one. How far away are the raindrops that produce it? It is hard to judge how far away a rain cloud is, especially if it's moving. The rainbow's distance extends from the nearest to the farthest raindrops that make up the colored light. The closest of these raindrops may be miles away. In the case of water spray from a lawn sprinkler in which a rainbow appears, you can reach right in and touch it. Or so it seems.
Can you go under a rainbow's arch and come out the other side? Not according to the laws of physics. A rainbow is all light and water. It is always in front of you while your back is to the sun. However, there is an old European belief that there is a pot of gold waiting at the end of the rainbow - if anyone can find it!
Do two people ever see the same rainbow? No. Why? Well, because the raindrops are constantly in motion, its appearance is always changing. Also, as the eyes of two people cannot occupy the same place in space at the same time, each observer sees a different rainbow. Each time you see a rainbow, it is unique in its own special way.
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(英語點津Annabel編輯)
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