Editing Cow tipping (section)

== Scientific study ==
[[File:Cow lying on side in field.jpg|thumb|left|A healthy cow lying on her side is not immobilized; she can rise whenever she chooses.]]
Some versions of the urban legend suggest that because cows sleep standing up, it is possible to approach them and push them over without the animals reacting.<ref name="Haines" /> However, cows only sleep lightly while standing up, and they are easily awakened.<ref name = Cow1>{{cite news |last = Malvern |first = Jack |title = Cow-Tipping Myth Hasn't Got a Leg to Stand On |newspaper = Times Online |url = https://www.thetimes.com/uk/science/article/cow-tipping-myth-hasnt-got-a-leg-to-stand-on-7p7b5zfsfn7 |access-date = October 28, 2006 |location = London |date = November 5, 2005 |archive-url = https://web.archive.org/web/20110629083548/http://www.timesonline.co.uk/tol/news/uk/article586737.ece |archive-date = June 29, 2011 |url-status = live }}</ref> They lie down to sleep deeply.<ref name=collins /> Furthermore, numerous sources have questioned the practice's feasibility, since most cows weigh over {{convert|450|kg|lb|abbr=off}} and easily resist any lesser force.<ref name = Cow1 /><ref>{{cite web |last = Semke |first = Matt |title = The Statics of Cow Tipping |publisher = University of Nebraska – Lincoln (UNL) College of Engineering and Mechanics Course Project |url = http://emweb.unl.edu/Mechanics-Pages/Matt-Semke/The%20Statics%20of%20Cow%20Tipping.htm |access-date = April 17, 2007 |url-status = live |archive-url = https://web.archive.org/web/20080827083454/http://emweb.unl.edu/Mechanics-Pages/Matt-Semke/The%20Statics%20of%20Cow%20Tipping.htm |archive-date = August 27, 2008 |df = mdy-all }}</ref>

A 2005 study led by Margo Lillie, a [[zoology|zoologist]] at the [[University of British Columbia]], and her student Tracy Boechler, concluded that tipping a cow would require a force of nearly {{convert|3000|N}}<ref name="Haines">{{cite news |last = Haines |first = Lester |title = Boffins Debunk Cow-Tipping Myth |newspaper = The Register |date = November 9, 2005 |access-date = November 30, 2012 |url = https://www.theregister.co.uk/2005/11/09/cow_tipping |url-status = live |archive-url = https://web.archive.org/web/20121031144516/http://www.theregister.co.uk/2005/11/09/cow_tipping/ |archive-date = October 31, 2012 |df = mdy-all }}</ref> and is therefore impossible to accomplish by a single person. Her calculations found that it would require more than four people to apply enough force to push over a cow,<ref name="Haines" /> based on an estimate that a single person could exert {{convert|660|N}} of force. However, since a cow can brace itself, Lillie and Boechler suggested that five or six people would, most likely, be needed.<ref name=collins /> Further, cattle are well aware of their surroundings and are very difficult to surprise, due to excellent senses of both smell and hearing.<ref name=collins>{{cite news |url = https://www.telegraph.co.uk/news/science/science-news/10289862/Cow-tipping-myth-dispelled.html |title = Cow Tipping Myth Dispelled |first = Nick |last = Collins |work = [[The Daily Telegraph]] |date = September 6, 2013 |access-date = May 18, 2016 |url-status = live |archive-url = https://web.archive.org/web/20160426021919/http://www.telegraph.co.uk/news/science/science-news/10289862/Cow-tipping-myth-dispelled.html |archive-date = April 26, 2016 |df = mdy-all }}</ref><ref name=Glenn>{{cite news |first = Eddie |last = Glenn |url = http://tahlequahdailypress.com/archive/x519330324 |title = Cow-Tipping: Myth or Reality? |work = Tahlequah Daily Press |date = December 15, 2006 |access-date = May 18, 2016 |archive-date = June 22, 2012 |archive-url = https://web.archive.org/web/20120622203359/http://tahlequahdailypress.com/archive/x519330324 |url-status = live }}</ref> Lillie and Boechler's analysis found that if a cow did not move, the principles of static physics suggest that two people might be able to tip a cow if its [[centre of mass]] were pushed over its hooves before the cow could react. However, cows are not rigid or unresponsive, and the faster humans have to move, the less force they can exert. Thus Lillie and Boechler concluded that it is unlikely that cows can actually be tipped over in this way.<ref name="Haines" /> Lillie stated, "It just makes the physics of it all, in my opinion, impossible."<ref name=collins />

Although biologist Steven Vogel agrees that it would take a force of about 3,000 newtons to push over a standing cow, he thinks that the study by Lillie and Boechler overestimates the pushing ability of an individual human.<ref name="Vogel" /> Using data from Cotterell and Kamminga, who estimated that humans exert a pushing force of 280 newtons,<ref>{{cite book |last1 = Cotterell |first1 = Brian |last2 = Kamminga |first2 = Johan |title = Mechanics of Pre-industrial Technology : Introduction to the Mechanics of Ancient and Traditional Material Culture |date = 1992 |publisher = Cambridge University Press |location = Cambridge |isbn = 978-0-521-42871-2 |url = https://books.google.com/books?id=0-xOM8y6Uc8C |via = Google Books |access-date = May 19, 2016 |archive-date = October 13, 2023 |archive-url = https://web.archive.org/web/20231013205258/https://books.google.com/books?id=0-xOM8y6Uc8C |url-status = live }}</ref> Vogel suggests that someone applying force at the requisite height to topple a cow might generate a maximum push of no more than 300 newtons. By this calculation, at least 10 people would be needed to tip over a non-reacting cow. However, this combined force requirement, he says, might not be the greatest impediment to such a prank. Standing cows are not asleep and, like other animals, have ever-vigilant reflexes. "If the cow does no more than modestly widen its stance without an overall shift of its center of gravity", he says, "about 4,000 newtons or 14 pushers would be needed—quite a challenge to deploy without angering the cow."<ref name="Vogel">{{cite book |last = Vogel |first = Steven |title = Glimpses of Creatures in Their Physical Worlds |publisher = Princeton University Press |year = 2009 |page = 238 |url = https://books.google.com/books?id=qaOi_huPdfsC |isbn = 978-0-691-13806-0 |access-date = May 19, 2016 |archive-date = October 13, 2023 |archive-url = https://web.archive.org/web/20231013205259/https://books.google.com/books?id=qaOi_huPdfsC |url-status = live }}</ref>