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
2024-10-24
26
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 all 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 eye must be speeded up, or the cat’s fall slowed down for the phenomenon to be observed. A century ago the 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 them extends them again, 【C17】______ he 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] 【C20】
选项
A、perception
B、experience
C、reception
D、experiment
答案
A
解析
B:经验、体验;C:接待、接纳;D:实验、试验。只有A“感觉、感知”符合句意。
转载请注明原文地址:https://tihaiku.com/zcyy/3815918.html
相关试题推荐
Humanbeingshave______themselvestoverydiverseenvironmentswiththehelpo
Humansareuniqueintheextenttowhichtheycanreflectonthemselvesand
Humansareuniqueintheextenttowhichtheycanreflectonthemselvesand
Humansareuniqueintheextenttowhichtheycanreflectonthemselvesand
Humansareuniqueintheextenttowhichtheycanreflectonthemselvesand
Humansareuniqueintheextenttowhichtheycanreflectonthemselvesand
Humansareuniqueintheextenttowhichtheycanreflectonthemselvesand
Humansareuniqueintheextenttowhichtheycanreflectonthemselvesand
Humansareuniqueintheextenttowhichtheycanreflectonthemselvesand
Humansareuniqueintheextenttowhichtheycanreflectonthemselvesand
随机试题
In1940,ErnestHemingwaypublishedthenovelentitled______whichisabouttheS
Americanculturehasnotbeenimmunetoculturalinfluencesfromoutside.Th
施工控制网建立 1)工程概述 ××核电二期工程是中国自行设计建造的大型商用压
按崩解时限检查法检查,普通片剂应在多长时间内崩解A.20min B.15min
国家对农村“五保户”给予的物质帮助属于()。A.社会保险 B.社会福利
“仓廪实而知礼节,衣食足而知荣辱。”这句话反映了人的需要具有( )A.整体性
超限效应,是指当人们所接受的刺激过多,过强或者作用时间过久时,引起的心理极不耐烦
(2014年真题)某居民企业为服装生产企业,因无法准确核算成本支出,被税务机关确
在工程施工中,总监理工程师应及时签发工程暂停令的情形有()。A.建设单位要
患者,9岁,学生。1月底因突起高热、剧烈头痛、恶心伴非喷射性呕吐1次入院。体检:
最新回复
(
0
)