首页
登录
职称英语
What do cats’ eyes and highway reflector signs have in common? They both act
What do cats’ eyes and highway reflector signs have in common? They both act
游客
2025-03-12
0
管理
问题
What do cats’ eyes and highway reflector signs have in common? They both act as retro-reflectors(反响反射器).
Almost everyone has noticed the frightening appearance of animals at night, as their eyes seem to glow in reflected light. One may think that just as reflective highway signs alert the motorists to many road hazards, so early man was often warned of danger by light from his campfire reflected in the eyes of lurking(潜伏)predators. In both cases, the light is ret-roreflected, giving it a particularly bright appearance.
The principles of retroreflection have been understood for centuries. However, it is only within the last fifty or sixty years, with the wide use of the automobile, that this area of optics(光学)has received important commercial application. Today, the uses of retroreflective materials are many. They are applied to bicycles and motor vehicles to make them more visible at night. And they assist pilots by improving the visibility of runway markers.
Large sums are spent for retroreflective materials, but purchasers have often found it difficult to specify performance for the materials they buy. Performance is of concern not only from the standpoint of the brightness of reflected light, but also from the standpoint of its color. It is important, for example, that the yellow hues(色调)in warning signals be of consistent color quality on all road signs so the driver can rely on color, as well as shape, to discern the signs’ meanings. Seven colors — silver, blue, yellow, red, green, brown and orange — are currently used for marking the interstate highway system. [br] The passage suggests that______.
选项
A、government scientists are developing inexpensive retroreflectors
B、the government manufactures retroreflective devices
C、retroreflective devices are widely used for public facilities
D、retroreflectors were first used to scare wild animals away
答案
C
解析
本题属于推理判断题。文章提到,机场跑道指向标(第三段最后一句)、道路标志牌(第四段第三句)、州际公路系统(第四段最后一句)等均采用了反向反射材料。可见,反向反射装置被广泛地应用于公共设施。所以选项C)为正确答案。
转载请注明原文地址:https://tihaiku.com/zcyy/3993515.html
相关试题推荐
______studentwithalittlecommonsenseshouldbeabletoanswerthequestion.
Believeitornot,opticalillusion(错觉)cancuthighwaycrashes.Japanisac
Believeitornot,opticalillusion(错觉)cancuthighwaycrashes.Japanisac
Believeitornot,opticalillusion(错觉)cancuthighwaycrashes.Japanisac
Whatdocats’eyesandhighwayreflectorsignshaveincommon?Theybothact
Whatdocats’eyesandhighwayreflectorsignshaveincommon?Theybothact
Theexpression"stateoftheart"becameascommonandpopularascomputersthem
Onetypeofpersonthatiscommoninmanycountriesistheonewhoalwaystr
Onetypeofpersonthatiscommoninmanycountriesistheonewhoalwaystr
Onetypeofpersonthatiscommoninmanycountriesistheonewhoalwaystr
随机试题
Shewasextremely______aboutexpressingheropinions.A、cautiousB、carefulC、worr
TeachersandresearchersofEnglishlanguageartshavebeenstrugglingwith
Text2Overthepastdecade,thousandsof
2013年,我国硕士研究生报录比为)A.3.1 B.3.2 C.3.3
以太网链路聚合技术是将()。A.多个逻辑链路聚合成一个物理链路 B.多个逻辑
A.5 B.6 C.7 D.8
小儿断奶时间宜在( )。A.2~3个月 B.4~5个月 C.6~7个月
膀胱癌典型临床表现为A.蛋白尿、尿频、尿急 B.血尿、腰腹绞痛、排尿中断 C
下列不属于企业财务状况风险的是()。 A.借款人在银行的存款有较大幅度下降
对奥美拉唑叙述正确的是A.可视作前药 B.具弱碱性和弱酸性 C.属于可逆性质
最新回复
(
0
)