id
type
0 (not classified)
status
30 (imported + raw text content deleted)
review version
0
cleanup version
0
pending deletion
0 (-)
created at
2025-11-15 02:01:01
updated at
2025-11-15 02:01:03
pol page id
pol status
0
pol hosts ticketing
pol hosts ecommerce
pol hosts finance
pol hosts crypto
pol hosts leak
pol hosts devel
pol hosts ugc
pol hosts klim
pol hosts builders
pol hosts self subdomains
pol hosts other subdomains
turnbull.dcs.st-and.ac.uk
pol hosts other domains
interactagram.com
pol updated
1767500438
url
https://aty.sdsu.edu/explain/optics/refr.html
url length
45
url crc
64175
url crc32
1479211695
location type
1 (url matches target location, page_location is empty)
canonical status
2 (missing canonical tag in html)
canonical page id
-
domain id
domain tld
2295
domain parts
0
originating warc id
-
originating url
https://data.commoncrawl.org/crawl-data/CC-MAIN-2025-33/segments/1754151280019.53/warc/CC-MAIN-20250808034803-20250808064803-00317.warc.gz
source type
11 (CommonCrawl)
server ip
Publication date
2025-08-08 05:34:09
Fetch attempts
0
Original html size
13610
Normalized and saved size
13610
title
Refraction
excerpt
content
Refraction Introduction For thousands of years, people have noticed that a straight stick placed obliquely in water appears to be broken at an angle where it enters the water. This is the origin of the term “refraction,” which means literally “broken back.” For about two thousand years, astronomers have known that heavenly bodies seen near the horizon appear slightly higher in the sky than they really are. This was attributed to refraction by the Earth's atmosphere; but it was not understood in detail until a couple of hundred years ago. This astronomical refraction, in its more extreme forms, is the cause of green flashes. Refraction in the atmosphere is complicated by the continuous change in density of the air. So let's begin by considering refraction of light at a plane boundary between two uniform media — say, air and water, or air and glass. (For the moment, we will ignore the variations of density in the air.) In the diagrams below, heavy lines represent “rays” of ...
author
updated
1767500438
block type
0
extracted fields
104
extracted bits
title
full content
content was extracted heuristically
detected location
0
detected language
1 (English)
category id
Other [en] (231)
index version
2025123101
paywall score
0
spam phrases
0
text nonlatin
0
text cyrillic
0
text characters
7727
text words
1760
text unique words
525
text lines
1
text sentences
75
text paragraphs
1
text words per sentence
23
text matched phrases
6
text matched dictionaries
3
links self subdomains
0
links other subdomains
1
links other domains
1
links spam adult
0
links spam random
0
links spam expired
0
links ext activities
1
links ext ecommerce
0
links ext finance
0
links ext crypto
0
links ext booking
0
links ext news
0
links ext leaks
0
links ext ugc
0
links ext klim
0
links ext generic
0
image author
featured image