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
42
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
BEHAVIORISMBehaviorismisaschoolofpsychology
Ifcategorized,employeescanberoughlydividedintothosewhoarealwayso
[originaltext]W:Oh,itisterrible!AbroadAerolinesArgentina’sflight386.
[originaltext]M:DoctorBrook,Ijustdon’tknowwhat’swrongwithmc.Ialways
施工组织设计应由()主持编制A、项目负责人 B、项目技术负责人 C、企业
2016年2月,国家外汇管理局发布《合格境外机构投资者境内证券投资外汇管理规定》
下列说法错误的是( )。A.资产证券化托管人是指为资产支持证券持有人之利益,按
患者女,26岁。性生活正常,婚后3年未孕,经夫妇双方检查,证实男方为无精症,女方
在平原地区的路基施工中,( )为主导工序。A.移挖作填 B.半填半挖 C.
对于二尖瓣关闭不全,下列说法不正确是A.可引起左房、左室扩大 B.风湿性损害最
最新回复
(
0
)