首页
外语
计算机
考研
公务员
职业资格
财经
工程
司法
医学
专升本
自考
实用职业技能
登录
外语
A、The quicker it vibrates, the greater the frequency of sound it produces. B、The slower it vibrates, the higher the frequency of
A、The quicker it vibrates, the greater the frequency of sound it produces. B、The slower it vibrates, the higher the frequency of
admin
2021-11-26
65
问题
Objects that are vibrating make sounds. Rhythmic sound vibrations produce sound waves which travel in every direction. The frequency of a sound is the number of waves that pass a given point each second. [9] The more rapidly an object vibrates, the greater the frequency of sound it makes. Frequency is measured in hertz. One hertz equals one sound wave per second. The frequency of sound determines the degree of highness or lowness of the sound. A high-pitched sound has a higher frequency than a low-pitched sound. [10] Humans hear sounds that have frequencies from about 20 hertz to 20.000 hertz. Sound with a frequency higher than 20,000 hertz is called ultrasound which is too high-pitched for humans to hear. However, many animals can hear ultrasound. Bats can hear higher sounds than any other animal. Some can hear up to 210,000 hertz. Bats send out lots of high-pitched squeaks and then listen to the echoes bouncing off things like insects. The shorter the time interval between the squeak and the echo, the closer they are to the insect. [11] Using sound to find or "see" things is called echolocation. Another animal that uses ultrasound is the dolphin. Dolphins can hear sounds up to about 150,000 hertz. Dolphins use sound waves to find food underwater. [11] They make clicking sounds that hit whatever is around them and then bounce back to the dolphins. Dolphins can send as many as 2,000 clicks per second. Dolphins’ ultrasound ability is so sensitive that they can detect small fish from 10 feet away.
9. What is the relationship between the vibration of an object and the frequency of its sound?
10. What sounds can humans hear?
11. According to the speaker, what is the phenomenon of echolocation?
选项
A、The quicker it vibrates, the greater the frequency of sound it produces.
B、The slower it vibrates, the higher the frequency of sound it produces.
C、The quicker it vibrates, the lower the frequency of sound it produces.
D、The frequency of sound it produces is not in proportion to the speed it vibrates.
答案
A
解析
短文提到,物体振动得越快,它制造的声音频率就越高。A为录音原文中the more…the greater结构的同义表达,故为正确答案。B与C意思相同,可同时排除;D明显与原文内容相冲突。
转载请注明原文地址:https://kaotiyun.com/show/G1x7777K
0
大学英语六级
相关试题推荐
Therecent,apparentlysuccessfulpredictionbymathematicalmodelsofanappearanceofEINino—thewarmoceancurrentthatperi
ProductionoftheAmbassador,thefirstcartobemadeinIndia,hasbeenhaltedbecauseoffallingdemand.ModelledontheMorr
Virtuallyeveryactivitythatentailsorfacilitatesin-personhumaninteractionseemstobeinthemidstofatotalmeltdownas
A、Higherprices.B、Moredemand.C、Lowerimportduties.D、Rapidgrowth.C细节辨认题。对话最后,女士明确指出,之所以家具的利润稍微高一点,是因为家具的关税低一些。因此答案为C)。
JustoffthecoastofSouthernCaliforniasitsSantaCruzIsland,whereamagicalcreaturecalledtheislandfox【C1】______Adeca
"Thedangerousthingaboutlyingispeopledon’tunderstandhowtheactchangesus,"saysDanAriely,behaviouralpsychologista
A、Itprovidestoomanyentertainmentprograms.B、Itisnotaseducationalasreadingbooks.C、Itmakesussitinitsfrontpassi
A、Shewantedtohaveafillingreplaced.B、Sheneededtohaveatoothpulled.C、Shecameinforadentalcheckup.D、Shecamefo
A、Hedoesgetamiracleinhislife.B、Heisonhisowntochangethecircumstances.C、Hetakesmoneyasnothingcomparedwithl
随机试题
5个学生——H、L、P、R和S中的每一个人将在三月份恰好参观3座城市M、T和V中的一座城市。已知以下条件:(1)S和P参观的城市互不相同。(2)H和R参观同一座城市。(3)L或者参观M或者参观T。(4)若P参观V,则
A.结节缝合B.连续缝合C.全层连续缝合+库兴氏缝合D.“8”字缝合E.荷包缝合断裂肌腱的缝合方式为
我国的《护士条例》中规定了护士的权利和义务。在以下的护士享有的权利的叙述中,不正确的是
某市机械进出口外贸公司2014年经营状况如下:(1)代理进口20批货物,共收取代理费55000元,代理成本15000元。(2)收购专用机械出口10批,取得出口收入1000000元人民币,采购时取得增值税专用发票注明货价230000元,增值税39100元
联合国的宗旨是维护世界和平与安全,促进国际合作与发展。因此,打击恐怖主义应该()。
某电影拍摄小组到一旅游景点拍摄,却对当地的生态环境造成了破坏,现领导要你调查此事,你怎么处理?
教育成就测验是属于()。
姐姐拿了第一名。
Cityresidentshaveahardtimetryingtoavoidcontactwithhazardouschemicalsindailylife.
Man:Ifyouaren’tdoinganythingparticular,shallweseethenewplayattheGrandTheatertonight?Woman:Soundsgreat.ButI
最新回复
(
0
)