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习题练习：Physics Unit12: Sound
本习题练习试卷来源于51fly国际课程 (https://51fly.win)， 为试卷打印版，您也可以在网站平台(https://autodiscover.51fly.win/)直接 访问本试卷的在线电子版并查看正确答案与解析，搜藏保存任意题目到收藏集。 访问方法: 平台首页左上角"通过试卷号快速访问"输入试卷号 70，并点击直达试卷；或浏览器地址栏内直接输入本试卷链接 https://autodiscover.51fly.win/test70.html  教师使用本平台可以抽题组卷或一键复制他人试卷，布置为在线考试或在线作业，全自动判分成绩一键排序导出，省时省力。
 作者: physics  发布日期: 2022-09-26 09:56    总分: 87分  得分: _____________

答题人: 游客未登录  开始时间: 22年08月07日 09:59  切换到: 整卷模式

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1#
 
单选题 ( 1.0 分) 切至整卷模式 搜藏此题  
  Which of the following is a fab3-p oaaxq+k0lse statement?

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2#
 
单选题 ( 1.0 分) 切至整卷模式 搜藏此题  
  In general, sound is conducted fastest throu9;( 7 . cx-hl+uyi6bu mliimcjgh

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3#
 
单选题 ( 1.0 分) 切至整卷模式 搜藏此题  
  What is the speed of sound in a steel r, oc7;co*r v2q;c udpgod?

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4#
 
单选题 ( 1.0 分) 切至整卷模式 搜藏此题  
  As the temperature of the air increases, what happens to tho dfyk )j70ix(be/az6 e velocity of sound? (As aoy bk6xf/7dj0(ez)isume that all other factors remain constant.)

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5#
 
单选题 ( 1.0 分) 切至整卷模式 搜藏此题  
  Compared to the velocity of a 400 Hz sound, the velocity of a 200 Hz so1msni 7l. (de3k(molt ejh7 d*und through (mm. ene(7hs* 1ldt7dloij3kair is

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6#
 
单选题 ( 1.0 分) 切至整卷模式 搜藏此题  
  Compared to the wavelength of a 400 Hz sound, the wavelength of a 200 Hz s*+us-3 g euee k. 8,(jtggcitround in air* , i.tc(ggu8rj3+es u-kgee t is

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7#
 
单选题 ( 1.0 分) 切至整卷模式 搜藏此题  
  Sound vibrations with frequenciqxhhpiea9, etmy:;*2-q h9qres greater than 20,000 Hz are called

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8#
 
单选题 ( 1.0 分) 切至整卷模式 搜藏此题  
  Sound vibrations with frequen)yiznr50yp y5,z6bsxm5e .di cy less than 20 Hz are called

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9#
 
单选题 ( 1.0 分) 切至整卷模式 搜藏此题  
  Suppose that a sound source is emitting waves uniformly in all dir-n hq:69q sppjections. If you move to a point twice as far away from the sourc p6shnp9q:j- qe, the frequency of the sound will be

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10#
 
单选题 ( 1.0 分) 切至整卷模式 搜藏此题  
  For spherically diverging was-np;o f i3xg ;2ht7faves, intensity is proportional to

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11#
 
单选题 ( 1.0 分) 切至整卷模式 搜藏此题  
  The intensity of a point source at a distance d from the source is I. What k ,4ha asv4)q+a; y4jmq xlnz3is the intensity at a distance 2d from tha zlh+4xk4q4)s3 a,a ny;v jqme source?

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12#
 
单选题 ( 1.0 分) 切至整卷模式 搜藏此题  
  You double your distance from a sound source that is radiating equally in cz7g6o (buo fphis) i0iyy ;goi):2/n all directioni27uis oh icof;gy )/p gb:6nz0o)(yis. What happens to the intensity of the sound? It reduces to

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13#
 
单选题 ( 1.0 分) 切至整卷模式 搜藏此题  
  You double your distance fx35e 1y+ctg rerom a sound source that is radiating equally in all directions. What happens to the intensity level of the sound? r+xe351e cgt y It drops by

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14#
 
单选题 ( 1.0 分) 切至整卷模式 搜藏此题  
  Which of the following increases as a sount k5lw 9w9lqfdw 0v92e(*igua d becomes louder?

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15#
 
单选题 ( 1.0 分) 切至整卷模式 搜藏此题  
  You move slowly toward a speaker emitting lpy nmr4lwdu,2ue i7.v :)+o la pure tone. What characteristic of the sound incrln l+u )uepyv7,w.:2mio4rl deases?

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16#
 
单选题 ( 1.0 分) 切至整卷模式 搜藏此题  
  What determines "loudness" of a musicam, spx/j4ab g1u0v5-4 /xingms gyse 4l note?

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17#
 
单选题 ( 1.0 分) 切至整卷模式 搜藏此题  
  What determines the "pitch" of a musical nax c+t+ 1pqt6rote?

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18#
 
单选题 ( 1.0 分) 切至整卷模式 搜藏此题  
  When sound passes fromaqoeal+gu* 8649xg c d air into water

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19#
 
单选题 ( 1.0 分) 切至整卷模式 搜藏此题  
  Pressure and displacdduyf.r (:rq on-;mb3vp v;-vement waves are

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20#
 
单选题 ( 1.0 分) 切至整卷模式 搜藏此题  
  Consider the standing wave on a guitar string and the sound wm(tum65s9m 3lmg i ez:;*prfc ave generated by the guitar as a resu(i9 m63uzcmstg:r m*pf5le ;m lt of this vibration. What do these two waves have in common?

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21#
 
单选题 ( 1.0 分) 切至整卷模式 搜藏此题  
  In a resonating pipe which is open at both ends, therb-mq*tpy0 flxvif )2-e

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22#
 
单选题 ( 1.0 分) 切至整卷模式 搜藏此题  
  Consider an open pipe of k9 0 (xl-u,vd lfk(nlzlength L. What are the wavelengths of the three lowest tones produced kzld ,9k(vx0( u-nlfl by this pipe?

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23#
 
单选题 ( 1.0 分) 切至整卷模式 搜藏此题  
  The lowest tone to resonate in an open pipe of length L is 200 Hz. Which one of6e1i6e gyc tf, the following freqf6y 1eet, ic6guencies will not resonate in the same pipe?

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24#
 
单选题 ( 1.0 分) 切至整卷模式 搜藏此题  
  An open pipe of length L is resonating at its fundamental frequency.z .pcwhe r f-9cf/2d7g Which stateme2e-cfphrc f g7.9 w/dznt is correct?

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25#
 
单选题 ( 1.0 分) 切至整卷模式 搜藏此题  
  In a resonating pipe which is opv) d-hk+y7vl shj 7tzh u*p5m3en at one end and closed at the other, there

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26#
 
单选题 ( 1.0 分) 切至整卷模式 搜藏此题  
  Consider a closed pipe of lengt;+g-kn0qhxqr: zonjvtur; jr95 h:-oh L. What are the wavelengths of the three lowest touqx 50t9+:j:rkr; -zjg-n ;oovrnh qhnes produced by this pipe?

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27#
 
单选题 ( 1.0 分) 切至整卷模式 搜藏此题  
  The lowest tone to resonate in a closed pipe of length L is 200 Hz. Whuk)(fty 3z y /ys /ikkxks*3ts+2,ov hich of the following k3kyf)s 3*t v/ 2y+z(,huo st ykk/ixsfrequencies will not resonate in that pipe?

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28#
 
单选题 ( 1.0 分) 切至整卷模式 搜藏此题  
  A pipe of length L closed at one end is resonating at its fex- 5pufo 2r5 d(f(hzqundamental frequency.hd 2xo ( z(-5fuqrfp5e Which statement is correct?

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29#
 
单选题 ( 1.0 分) 切至整卷模式 搜藏此题  
  A person stands between two sc4mm*xd 1z h9mcuju)9zl29jmpeakers driven by the same source. Each speaker produces a tone with a frequency of 200 Hz on a day when the speed of sound is 330 m/s. T*m zcdj c9mm h)j94xlu9um2z1he person is
1.65 m from one speaker and 4.95 m from the other. What type of interference does the person sense?

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30#
 
单选题 ( 1.0 分) 切至整卷模式 搜藏此题  
  In order to produce beat t+ trxqp27h*ms, the two sound waves should have

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31#
 
单选题 ( 1.0 分) 切至整卷模式 搜藏此题  
  Two pure tones are sounded together and a particular beatus8jprhv;o,k/zy :dlg) 6 f v9 frequency is heard. What happens to the beat frequency if the frequency of one of the s/j;fol 8):dvuhpvzy96 rk ,gtones is increased?

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32#
 
单选题 ( 1.0 分) 切至整卷模式 搜藏此题  
  The Doppler shift expla ybm(par*)i:oi:hylgnz :d(3ins

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33#
 
单选题 ( 1.0 分) 切至整卷模式 搜藏此题  
  A sound source approaches a stat8bk *0.9pcehuj sxnu- ionary observer. The frequency heard by the obsehes-u p b8j x0u9*.kcnrver is

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34#
 
单选题 ( 1.0 分) 切至整卷模式 搜藏此题  
  A sound source departxu jww.9lnc qn* h9)o4x-ik )vs from a stationary observer. The frequency heard by the obse.u ql9 wv-kh)xjn*4wixnc9 o)rver is

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35#
 
单选题 ( 1.0 分) 切至整卷模式 搜藏此题  
  If a jet plane were to double its MACH-speed, its half-awf:gds ;(u5f cf1 gy0angle will decrease by a factor of;gf ud:f g1s ayw50f(c:

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36#
 
单选题 ( 1.0 分) 切至整卷模式 搜藏此题  
  The speed of an ultrasonic sound of frequency 45 kHz in air is u i8q5fkip*t kj4 oo19dl)3wu 352 m/s. What is the air ti3)*qk8k lfpt59ju u 4oiow1 demperature?

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37#
 
单选题 ( 1.0 分) 切至整卷模式 搜藏此题  
  What is the ratio of the spe vol8w4 6o cje-1721udlx tioked of sound in air at $0 \; ^{\circ}C$ to the speed at $100 \; ^{\circ}C$?

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38#
 
单选题 ( 1.0 分) 切至整卷模式 搜藏此题  
  On a day when the speed of sound in air is 340 m/s, a batg2qsfq )l-9 i6wmu x.s emits a shriek whose echo reaches it 0.0250 s later. Hosquq w.-)s6lf 2 x9gimw far away was the object that reflected back the sound?

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39#
 
单选题 ( 1.0 分) 切至整卷模式 搜藏此题  
  You shout at a cliff, and hear ev.o-+r;t/nxeg cz- i hy7w-ethe echo in 4.00 s. The temperature is $0 \; ^{\circ}C$. How far away is the cliff?

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40#
 
单选题 ( 1.0 分) 切至整卷模式 搜藏此题  
  If you hear thunder 5.0 s after seeing a flash of lightning, th r 54uv9sty rfa+-4m-hfjtp)me distance to the lightningu pf9)vr4yt 4hs-m5f+t-ramj strike is about

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41#
 
单选题 ( 1.0 分) 切至整卷模式 搜藏此题  
  An echo is heard 2.0 s from a cliff on a day the temperaturs(enjontk+u,t q1, ) le is $15 \; ^{\circ}C$. Approximately how far is the cliff from the observer?

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42#
 
单选题 ( 1.0 分) 切至整卷模式 搜藏此题  
  On a $30 \; ^{\circ}C$ day, there is an explosion. The sound is heard 3.4 s after seeing the flash. How far away was the explosion?

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43#
 
单选题 ( 1.0 分) 切至整卷模式 搜藏此题  
  You drop a stone into a q- /+iujavt62fta kicb0d. t.deep well and hear the splash 2.5 s later. How deep is the well? (Ignore air resistance, and assbiu 0vk 6c .+.fit qt/-aad2tjume the velocity of sound is 340 m/s.)

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44#
 
单选题 ( 1.0 分) 切至整卷模式 搜藏此题  
  The wavelength in air of a sound wave of frequency 500 Hz ab*ncr.1bx .e is

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45#
 
单选题 ( 1.0 分) 切至整卷模式 搜藏此题  
  Sound traveling in air0g z+qw ycp q 7yg226fhi29ffc at $23 \; ^{\circ}C$ enters a cold front where the air temperature is $2 \; ^{\circ}C$. If the sound frequency is 1500 Hz, determine the wavelength in the warmer air and in the colder air.

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46#
 
单选题 ( 1.0 分) 切至整卷模式 搜藏此题  
  What is the intensity level qi4 ,um tkpx)j9llirk)/4v, xof a sound with intensity $10^{-3} \; W/m^{2}$?

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47#
 
单选题 ( 1.0 分) 切至整卷模式 搜藏此题  
  What is the intensity of a 70-dB sox6qictn )mlm7 ss 9:2zund?

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48#
 
单选题 ( 1.0 分) 切至整卷模式 搜藏此题  
  What is the ratio of the intensities of two b h/m-6tx.lvvvw+u txi/1 e z.sounds with intensity levels of 70 dzv.tiv+th xu./bv/le1mw 6-x B and 40 dB?

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49#
 
单选题 ( 1.0 分) 切至整卷模式 搜藏此题  
  The intensity level by 15 engines in a garage is 100 dB. What is the intensity mc+q33u t .l3g xs7vpzlevel genetq+ gpl3.vzc sm7 33xurated by one engine?

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50#
 
单选题 ( 1.0 分) 切至整卷模式 搜藏此题  
  The intensity at a distance of 6.0 m from a source gaq a(9r;6lukbpo-50 xi yu6jthat is radiating equally in all directiog0;i(pobaxyarlu6 5k ju -6q9 ns is
$6.0 \times 10^{-10} \; W/m^{2}$. What is the power emitted by the source?

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51#
 
单选题 ( 1.0 分) 切至整卷模式 搜藏此题  
  The intensity at a distance of 6.0 m from a source that is radiating equc8 i).qkosxg14ujl2 aally in all direloq4x 8)1s gkjc2a.iu ctions is
$6.0 \times 10^{-10} \; W/m^{2}$. What is the intensity level in dB?

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52#
 
单选题 ( 1.0 分) 切至整卷模式 搜藏此题  
  A barking dog delivers about 1 mW of power, which is assumed a1:(yzoix 8:plfrs) a to be uniformly distri(yrf xl 1a::)zs8a opibuted in all directions. What is the intensity level at a distance 5.00 m from the dog?

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53#
 
单选题 ( 1.0 分) 切至整卷模式 搜藏此题  
  The intensity level is 65 dB at a distance 5.00 m fromky: 1b3y)1xv4oe wsa x a barking dog. What would be the intensity level if two identical dogs very close to eachok1ay4wbxy:) se3v 1 x other are barking?

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54#
 
单选题 ( 1.0 分) 切至整卷模式 搜藏此题  
  At a distance of 15 m from a so* 2x ch,bhzt928/ ky;ujc m0pa 3xxzfpund source the intensity level is 60 dB. What is the intensity level (in dB) at a point 2.0 m from the source? Assume that the source radzx 80t2/9 c;m3z xpc2h*yk,x afph bjuiates equally in all directions.

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55#
 
单选题 ( 1.0 分) 切至整卷模式 搜藏此题  
  The sound intensity level 5.0 m from a poix+uhqd i-c,*ip 4wud,nt source is 95 dB. At what distance will it be 75 d ic,-uwx d,d*+uipq4h B?

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56#
 
单选题 ( 1.0 分) 切至整卷模式 搜藏此题  
  The third harmonic of a complex tone has a frequency of 1200 Hz. What5o9svumb37 sy is the frequency o5 suv7m9osy3bf the fourth harmonic?

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57#
 
单选题 ( 1.0 分) 切至整卷模式 搜藏此题  
  The frequency of the third harmonic of an open pipe is 90:j7:pf1 f4do/ x eq8v/j+aefnyrkj )d0 Hz. What is the length of ejfdany d/7vf::r1x q)/ fjoe+ j4k8pthe pipe?

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58#
 
单选题 ( 1.0 分) 切至整卷模式 搜藏此题  
  The lowest tone to resonate in an open pipe of length L is 400 Hz. What isrw*fp;qai6a71 93lpfm ,hgde the fraf ag1imq,6 d73rlpw9;*h pefequency of the lowest tone that will resonate in an open pipe of length 2L?

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59#
 
单选题 ( 1.0 分) 切至整卷模式 搜藏此题  
  An organ pipe open at both ends has a length of 0.80 m. If the g(9i8qk/v(uvws:q 79 boc2o j nt;zzmvelocity of sound in air is 340 m/s, what is the frequency of the second harmonic?gkvu tjz nw2bo :voq/s9((9zi7;8 mcq

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60#
 
单选题 ( 1.0 分) 切至整卷模式 搜藏此题  
  A 3.00-m long pipe is in a room wes h(s lw56m(ivj j:5shere the temperature is $20 \; ^{\circ}C$. What is the fundamental
frequency if the pipe is open at both ends?

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61#
 
单选题 ( 1.0 分) 切至整卷模式 搜藏此题  
  The fundamental frequency ,qp8la v z4zm+in a pipe closed at one end is 330 Hz. What is the frequency of the third harmonic?z+z,8a4 vplqm

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62#
 
单选题 ( 1.0 分) 切至整卷模式 搜藏此题  
  What is the length of the shortest pipe closed on one end that will have a wwi.11;w+ly m3peg dzfundamental fr gzl1wi+py d.w; 1m3weequency of 60 Hz on a day when the velocity of sound is 340 m/s?

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63#
 
单选题 ( 1.0 分) 切至整卷模式 搜藏此题  
  A 3.00-m long pipe is in a room where the temperature tcog9if y:aca8gb,64 is $20 \; ^{\circ}C$. What is the fundamental frequency if the pipe is closed at one end?

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64#
 
单选题 ( 1.0 分) 切至整卷模式 搜藏此题  
  A 3.00-m long pipe is in a room where the temperaturv)hjq6 f - x6fc4xm:due is $20 \; ^{\circ}C$. What is the frequency of the second harmonic if the pipe is closed at one end?

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65#
 
单选题 ( 1.0 分) 切至整卷模式 搜藏此题  
  A closed organ pipe of length 0.75 m is played when the speed of sound in 05ryg+3 wauxc air is 340 m/s. What is the funwgx+rcu 3 a05ydamental frequency?

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66#
 
单选题 ( 1.0 分) 切至整卷模式 搜藏此题  
  Consider two pipes of the same length: one is o0 e,,x6iey. qwg.mscl pen and the other is closed on onecs.,e,.il q x6mwy0ge end. If the fundamental frequency of the open pipe is 300 Hz, what is the fundamental frequency of the closed pipe?

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67#
 
单选题 ( 1.0 分) 切至整卷模式 搜藏此题  
  Two adjacent sources each emit a frequency of 800 Hz in air where the q-uig6bgln;q 9g7+g rvelocity of sound is 340 m/s. How muchbg+7; -g6lnq i 9grgqu farther back would source 1 have to be moved so an observer in front of the sources would hear no sound?

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68#
 
单选题 ( 1.0 分) 切至整卷模式 搜藏此题  
  Two speakers are placed side by side and driven b;gt frmu5h63l( (tvbqd g7my :y the same frequency of 500 Hz. If the distance from a person to one speaker is 5.00 m and the person detects little or no sound, which of the followigml7:vbfuhrmg5 (q 3tt6;dy ( ng is a possible the distance from the person to the other speaker? (The sound speed is 340 m/s.)

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69#
 
单选题 ( 1.0 分) 切至整卷模式 搜藏此题  
  Two tunes have frequencies of 440 Hz and 444 Hz. What is the beat .py:8wg2n.vb/t(nhv zy 8g zsfrequency?

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70#
 
单选题 ( 1.0 分) 切至整卷模式 搜藏此题  
  A music tuner uses a 550-Hz tuning fork to tune the frequ2aj6sa7l5cnuf; : ah rency of a musical instrument. If the tuner hears a beat frequency of 2 Hz, what is the frequencfha7r6l;a u:n c2j5asy of the instrument?

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71#
 
单选题 ( 1.0 分) 切至整卷模式 搜藏此题  
  The wavelengths of the sounds produced by two horns are 6 m and 7 m respectively btr b.;wigv-2. What beat frequency is heard when the horns are sounded on a day when the velocity of irb.wg;v -tb2sound is 340 m/s?

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72#
 
单选题 ( 1.0 分) 切至整卷模式 搜藏此题  
  The corresponding violin strings on two violins in an orchestra areob))nir 7u0e qye4 ,vj found to produce a beat frequency of 2 Hz when a frequency of 660 Hz is played. What percentage change in the tension of one ,o0ieju vqb 4)ey7 )rnof the strings would bring them to the same frequency?

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73#
 
单选题 ( 1.0 分) 切至整卷模式 搜藏此题  
  An observer approaches a stationary 1000-Hz sound source at twice ra3;8t0mog :s c s- uab2czng8/yjx ;bthe speed of sounu g8y;o 8jc;r2n-amgtsbsbza 03 :c x/d. The observer hears a frequency of

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74#
 
单选题 ( 1.0 分) 切至整卷模式 搜藏此题  
  A sound source (normal frequency of 1000 Hz) approaches a stamb3xj6z6h+b7)ae mbf( jy-kl tionary observer at one-half the speed of sound. Th(bjmk mxl)eaf 36 +-ybz7h bj6e observer hears a frequency of

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75#
 
单选题 ( 1.0 分) 切至整卷模式 搜藏此题  
  A sound has a frequency of 1000 Hz. If aqe bc8 nd;v0r3 listener moves with a speed of 30 m/s away from the source, what is the frequency heard by the observer? (The sound speed is 34d 0r bc;3qev8n0 m/s.)

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76#
 
单选题 ( 1.0 分) 切至整卷模式 搜藏此题  
  A police car has an 800-Hz siren. It ishlqye : z-( mxbxtn7p+j kk+95 traveling at 35 m/s on a day when the speed of sound through air is 3m jy+b5k ( qk:+p9zx7ln x-eht40 m/s. The car approaches and passes an observer who is standing along the roadside. What change of frequency does the observer hear?

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77#
 
单选题 ( 1.0 分) 切至整卷模式 搜藏此题  
  What is the frequency heard by a stationa+ )xdobeh(. hery observer when a train approaches with a speed of 30 m/s. The frequency of the train horn is 600 Hzd b)oee+(x .hh and the speed of sound is 340 m/s.

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78#
 
单选题 ( 1.0 分) 切至整卷模式 搜藏此题  
  A train is traveling toward you at 120 ko- ,; oho. 4t;fi7dme flum494h;bsu5svwmbfm/h. The train blows its 400-Hz whistle. Take the speed of sound to be 340 m/s. W9ffi om,;u t-h ;;b4sbvh.wlu5s4o 7moem4 dfhat frequency do you hear?

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79#
 
单选题 ( 1.0 分) 切至整卷模式 搜藏此题  
  You are moving at 120 km/h toward a stationar wh2l /m+u hf3ut3yt1ry train. The train blows its 400-Hz whistle. Take the speed of sound to be 340 m/s. What frequencruh +w/uf hltm3y13t2y do you hear?

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80#
 
单选题 ( 1.0 分) 切至整卷模式 搜藏此题  
  A train is traveling away from you at 120 km/h. kcmi2+c + v8hlko q:1j The train blows its 400-Hz whistle.vc+k8 :21 kj+imlcho q Take the speed of sound to be 340 m/s. What frequency do you hear?

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81#
 
单选题 ( 1.0 分) 切至整卷模式 搜藏此题  
  A train is traveling away from you a oz( 5zrcb8t5kt 120 km/h. It blows its whistle, and you hear a tone of 400 Hz. Take the speed of sound to be 340 m/s. What is the actual freqtbrz8k c 5o5z(uency of the whistle?

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82#
 
单选题 ( 1.0 分) 切至整卷模式 搜藏此题  
  The frequency of a train horn is 500 Hz. Assume the speed of sound in lw/m.c 8ksc(xair is 340 m/s. What is the frequency heard by an observer if thcc smlk8w./ x(e observer is moving away from the train with a speed of 30.0 m/s?

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83#
 
单选题 ( 1.0 分) 切至整卷模式 搜藏此题  
  The frequency of a train a2o*x fhoi6,ja 29 qpbhorn is 500 Hz. Assume the speed of sound in air is 340 m/s. What is the frequency heard by an observer if the observer*f22 bxi oq9, ajhoa6p is approaching the train with a speed of 30.0 m/s?

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84#
 
单选题 ( 1.0 分) 切至整卷模式 搜藏此题  
  Sonar is used to determine the speed of an object. A 40-kHz signal in oc+2oaaaj l-nla(;7 s sent out, and a 42-kHz signal is returned. A 2l;nao-j nlo+a7(aca ssume the speed of sound is 345 m/s. How fast is the object moving?

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85#
 
单选题 ( 1.0 分) 切至整卷模式 搜藏此题  
  The half angle of the conical shock wave produced by a supersonic airurze/f 8)y9uu craft is $60^{\circ}$. What is the Mach number of the aircraft?

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86#
 
单选题 ( 1.0 分) 切至整卷模式 搜藏此题  
  A jet flies at a speed of Mach 1.4. What is the half-angle of the conicohnr:er86 9ug2 u5*d vm)dxobal shock wave formedou*hm2x 6rvd:on5dug8 ) r eb9?

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87#
 
单选题 ( 1.0 分) 切至整卷模式 搜藏此题  
  The Concord airplane flies from the Und 9s0cv5;qov zited States to Europe with a Mach number of 1.05 where the air scd0v5 o9;vqz temperature is $5.0 \; ^{\circ}C$. What is the speed of the plane?

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