首页
登录
职称英语
The ability of falling cats to right themselves in midair and land on their
The ability of falling cats to right themselves in midair and land on their
游客
2023-11-23
39
管理
问题
The ability of falling cats to right themselves in midair and land on their feet has been a source of wonder for ages. Biologists long regarded it as an example of【C1】______ by natural selection, but for physicists it bordered on the miraculous. Newton’s laws of motion【C2】______ that the total amount of spin of a body cannot change【C3】______ an external torque speeds it up or slows it down. If a cat has no spin when it is released and experiences no external torque, it ought not to be able to 【C4】______ as it falls.
In the speed of its execution, the【C5】______ of a tumbling cat resembles a magician’s trick. The gyrations of the cat in midair are【C6】______ fast for the human eye to follow, so the process is obscured. 【C7】______ the speeded up, or the cat’s fall slowed down for the phenomenon to be former was accomplished 【C8】______ high-speed photography using equipment now【C9】______ in any pharmacy. But in the nineteenth century the【C10】______ on film of a falling cat constituted ascientific experiment.
The experiment was described in a paper presented to the Paris Academy in 1894. Two sequences of twenty photographs【C11】______ , one from the side and one from behind,【C12】______ a white cat in the act of righting itself. Grainy and quaint【C13】______ they are, the photos show that the cat was dropped upside down, with no initial spin, and still landed on its feet. Careful analysis of the photos reveals the secret. As the cat rotates the front of its body【C14】______ , the rear and tail twist counterclockwise,【C15】______ the total spin remains zero,【C16】______ Newton’s laws. Halfway down, the cat pulls in its legs before reversing its twist and then extends them again,【C17】______ the desired end result. The explanation was that while no body can acquire spin without torque, a flexible one can readily change its【C18】______ Cats know this instinctively, but scientists could not be sure how it happened【C19】______ they increased the speed of their【C20】______ a thousand fold. [br] 【C6】
选项
A、so
B、much
C、rather
D、too
答案
D
解析
转载请注明原文地址:https://tihaiku.com/zcyy/3213069.html
相关试题推荐
Inmanycountries,whenpeoplegivetheirname,theyrefertothemselvesusin
Inmanycountries,whenpeoplegivetheirname,theyrefertothemselvesusin
Inmanycountries,whenpeoplegivetheirname,theyrefertothemselvesusin
Inmanycountries,whenpeoplegivetheirname,theyrefertothemselvesusin
Inmanycountries,whenpeoplegivetheirname,theyrefertothemselvesusin
Inmanycountries,whenpeoplegivetheirname,theyrefertothemselvesusin
PassageTwo(1)TheAmericanDream,definedastheabilityofeveryU.
Humanity’shighlydevelopedabilitytocommunicateverballyisouressence.
Humanity’shighlydevelopedabilitytocommunicateverballyisouressence.
Humanity’shighlydevelopedabilitytocommunicateverballyisouressence.
随机试题
[originaltext]Wehaven’thiredanewtechnicianyet,havewe?(A)No,youhave
[originaltext]Dr.LynneMoorehaspublishedoverfitlypapersandabookon
Formostpeoplewhohavesleepingtroubles,whichofthefollowingisthemostu
“神乐”属于()国家的舞蹈A.韩国 B.日本 C.朝鲜 D.中国
珍稀、濒危陆生动物和保护有价值的陆生动物的栖息地受到破坏或生境条件改变,可采取的
对于一个行业来说,潜在的进入者或新加入者会带来新的生产能力,带来新的物资资源,从
患者男,27岁。因车祸紧急入院治疗。患者神志不清,经检查为脑出血伴颅脑骨折。在临
彼得·德鲁克认为:“领导者的唯一定义就是其后面的追随者。一些人是思想家,一些人是
某女,49岁,经血非时而下,出血量多,淋漓不尽,色淡质稀,两目干涩,腰膝酸软,面
(2019年真题)下列建设工程进度影响因素中,属于业主因素的有( )。A.提供的
最新回复
(
0
)