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
2023-11-20
20
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 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 a scientific 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 thousandfold. [br] 【C20】
选项
A、perception
B、experience
C、reception
D、experiment
答案
A
解析
B项的意思是“经验,体验”;C项的意思是“接待,接纳”;D项的意思是“实验,试验”。只有A项“感觉,感知”符合句意。
转载请注明原文地址:https://tihaiku.com/zcyy/3204577.html
相关试题推荐
Humanity’shighlydevelopedabilitytocommunicateverballyisouressence.
Humanity’shighlydevelopedabilitytocommunicateverballyisouressence.
Humanity’shighlydevelopedabilitytocommunicateverballyisouressence.
Humanity’shighlydevelopedabilitytocommunicateverballyisouressence.
Humanity’shighlydevelopedabilitytocommunicateverballyisouressence.
Allpeoplehavesomeabilitytomanagetheirhealthandthehealthofthose
Allpeoplehavesomeabilitytomanagetheirhealthandthehealthofthose
Allpeoplehavesomeabilitytomanagetheirhealthandthehealthofthose
Allpeoplehavesomeabilitytomanagetheirhealthandthehealthofthose
Allpeoplehavesomeabilitytomanagetheirhealthandthehealthofthose
随机试题
Inmoderntimes,severalpeople______(在那瀑布上走过,他们大多数是有意的).havegoneoverthatf
[audioFiles]audio_eufm_j01_106(200910)[/audioFiles]A、She’llmakeabetterwebsi
把收集到的原始质量数据按照一定的目的加以分类整理,再据此进行质量分析的质量分析图
任何一家市场参与者在进行买断式回购交易时单只券种的待返售债券余额应小于该只债券流
在财产保险合同有效期内,保险标的的危险程度显著增加的,被保险人应当按照合同约定及
多台电动机启动时应()。 (A)按容量从小到大启动;(B)逐一启
某机械加工企业下设四个生产车间生产加工同种类型和型号的产品,并以人均产量评价劳动
下面给定的是纸盒外表面的展开图,右边哪一项能由它折叠而成?请把它找出来。
《中药大辞典》载药A.约1746种 B.1892种 C.365种 D.57
患者,男,40岁,体健,每日吸烟1包,诊断为慢性牙周炎,经牙周系统及配合袋内局部
最新回复
(
0
)