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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://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://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 followin)r vuq i e6e g0k*;im eizsf8c/nd5d,8g is a false 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 cq1rjy- 8i*besj7 x(fg onducted fastest through

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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 soun el576iwh qsrbbvn l4v.31zg)d in a steel rod?

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4#
 
单选题 ( 1.0 分) 切至整卷模式 搜藏此题  
  As the temperature oq)jbvv 3jxky-6og1 k9h0gh9 r f the air increases, what happens to the velocity of sound? (Assume tha9bohkqhjv0gg)-jx 1 3y9vrk6t 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 2 m,p;zmz7dx nlf0 q5bp( r-+rph(e.4iyom9jo00 Hz sound through air isp50.rzoiem- yhqm o;xnr d7jb pzp9,+4(lm(f

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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, thk*o + gwiw-y:le wavelength of a 200 Hz sound in wkwilg:y+*-o air 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 br 4v-yepqrv+jc7-vy:49 rdp frequencies 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 frequency less than 20 Hz are / gy)xpbno5x- 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 wxb cc*f; glb-)oy5vg/aves uniformly in all directions. If you move to a point5- /lycbxov);cggf *b twice as far away from the source, 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 wai(k tpb. pp5t 0;uvyo*ves, 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 ua hb8xe111do o99:mn 7 tpemcf4cq*na distance d from the source is I. What is the intensity at a distanc 9hof t*qn: 8oe1 c1 xdbmuae97m14pnce 2d from the 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 all di 6 ybdl 4exq(mkj7 l-)zqtl9j8rections. What happens to the i xj l6ek )4qqmydzlb78-(9tjlntensity 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 from a sound source that is radiating equallyky 7 f zhj-jkr7(hx95i in all directions. What happ(hzj 7kfhjri79- k xy5ens to the intensity level of the sound? 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 soa.;+w37gorax y/v; t fjfgs,mund 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 a pure tone. What charad x fkl56gu2 wr9*hh.scteristic of the sound s2.5dkrw fx6g *lu hh9increases?

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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 muspty- :gxv x:6yt*qo,q (irwh6l* 0zba b( mx.tical 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" o,: m1ti184wdxxcvm nyf a musical note?

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18#
 
单选题 ( 1.0 分) 切至整卷模式 搜藏此题  
  When sound passes from ail+yzh;d elb g*c:-5(u2jk sp mr 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 displacemosz7dlh ( (gre-*bk+m ent 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 arqrq.qf+,h 8 s guitar string and the sound wave generated by the guitar as a result of this vibration. What do these r+q8. hsfqq,rtwo 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 bnp *0: fch7bdnoth ends, there

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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 length L. What are the wavelengthsbc no,*+ mmt+s of the three lowest tones produc+cm mt,+sn*boed 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 pi2q*liljrdk tu ++ 40zape of length L is 200 Hz. Which one of the following frequencies will not resonate in the same iq* l0d4tzk aj 2+rl+upipe?

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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 tqsymut8+h:r+w6 8;b ,2r n aja8czupfrequency. Which statet,+sw+p 8m;ync h a urru8 zqj68:tab2ment 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 open at one end and closecpmkfg)bqo-v4 y-w r2s .kri511mn z:cn6o 5md 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 length L. ydsz* 8 7oa0qa What are the wavelengths of the three lowest tones pro*8 q sa0yd7zoaduced 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 resonatecvoqj8dji9 ;)npn0 7i in a closed pipe of length L is 200 Hz. Which of the following frequendv;9jnio 0 qin87 jp)ccies 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 fundamental frequency3q ,e(feh m)hm. Whicm(hqee h 3m),fh 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 speakers driven by the same source. Eapz bk:/v*4r ntch speaker produces a tone with a frequency of 200 Hz on a day when the speed of sound is 330 m/s. The pers4 vrk *ptb:nz/on 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 w.g qe3,to-v1or hp 2b,a0okh1zal,n beats, 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 beat frequ5y 08cnwb4 zw4osrr e(3rbcz5ency is heard. What happens to the beat frequency if the frequency of one of the tones is ibn sy5e5w408bzc rco4 zrw3r(ncreased?

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32#
 
单选题 ( 1.0 分) 切至整卷模式 搜藏此题  
  The Doppler shift explains s0b3uv f(tgs7

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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 stationaryrv n*v3gxw9ob5yn ;-oq2: e om observer. The frequency heard by the observer i 5 3vovxn2r*-ny;e9mwo:boq g s

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34#
 
单选题 ( 1.0 分) 切至整卷模式 搜藏此题  
  A sound source depar.yd3+) zw(y mksj 8azuts from a stationary observer. The frequency heard by the observ8yzudam .y(3z)j kws+er 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 iw d) tixk5pkjx rw0x, 2e24/qcts MACH-speed, its half-angle will decrease by a feci xx jp ,d2rw)54q0t2wk/ kxactor of:

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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 -d w*nqse3ih8 45 kHz in air is 352 m/s. What is the air tempera8-d*iqh3 wn esture?

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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 speed of sound in bp)csk 0 xz.w;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/(ix/wm2 )dmygf;i nslbb k714s, a bat emits a shriek whose echo reaches it 0.0250 s later. How (gixbmk 4 7lsdmw12i f)/b ny;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(/vfknaw qru6i15lm6 the 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 sr 9wuhs4 ++ihd8e km0v after seeing a flash of lightning, the distance to the lightninvmwsrhh k+ u8940+i deg 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 ths9b+nj-pz w*axyu j9 5e temperature 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 deep well and hear the splash 2.5 s later. k ,piw+l kt-z3How deep is the well? (Ignore air resistance, and assume the veloc+l,-kkzw ti3pity 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 is xz tjj drb8/*4va:f8k*vmsk9

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45#
 
单选题 ( 1.0 分) 切至整卷模式 搜藏此题  
  Sound traveling in air ahsk* k468gkj:dmm .5wp ts/pvp-, hlbt $23 \; ^{\circ}C$ 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 of a sound with intensity6gk;( b so-yvg-6msuusb, /wj $10^{-3} \; W/m^{2}$?

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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-dm0a ):dwbn;ldB sound?

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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 intensitie7b4ukmmixgik)mt07- s of two sounds with intensity levels of 70 dB and 40-mk)iigxb7u 0 mmkt4 7 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 i1f* g6hbl /vgnntensity lef1b/6 *nvgh lgvel generated 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 that1qal;;r8uunit z j -upt3rw96 is radiating equally in all directions iiu u1aw8 nt ;;9tpj- rrz6u3qls
$6.0 \times 10^{-10} \; W/m^{2}$. 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 radiatibil0fs(1g ss8efb f*3ng equally in all directigs0 s81*f ef(lfi bbs3ons 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 ass2fu91r ,55vutem-sjra olz (x umed to be uniformly distributed in all directions. What is the intensity level at a distance 5.00 m av2o el5-uz,rrf9 (1mtx5jusfrom 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 :2pk( k8 :rtpbuzz* tavzlci x02r*g,distance 5.00 m from a barking dog. What woul u*2 apz2kczzp gblrt:tr0i:8k( *,xvd be the intensity level if two identical dogs very close to each 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 sound source the intensity 3c;sh q *1arhulevel is 60 dB. What is the intensity level (in dB) at a point 2.0 m from the source? Assume that the ars;u *1chh3q source radiates 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 fu6: r3r8nsz r.a8x tkrrom a point source is 95 dB. At what distance will it be 75 dB?u3t8:8rk.asr n 6xrrz

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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. What is the f i t 4u+6krx txy84ga-6wt6gewrequenketit4gt u4+ g yw6 x6r8awx-6cy of 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 900 Hz. What5nfjbj hl9sd764 i4nk is the length of9di5f6s4n lb7j khj4 n the 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. Whatiaan28uvw -o4 is the frequency of the lowest tone that will 8a4 a 2-iuvownresonate 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 velocity of sou00j-l9w(ak y0iucbjo *1(vyf0awakx nd in aiafkwba(j90k j0y( 0i u0xy lv1 acwo*-r is 340 m/s, what is the frequency of the second harmonic?

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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 where thse8r g3:os)zr1j-d; ; tdwhbne 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 i bv2 dr+y .72un7iysapn a pipe closed at one end is 330 Hz. What is the frequency of the thi7dvru2a.npi+ b y s27yrd harmonic?

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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 3 iizch*au1dq-/ym1n the shortest pipe closed on one end that will have a fundamental frequency of 60 Hz on a day when t n/ hucydz1-mai i*3q1he 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 iah5wi5 k- (gso( */wuk6cilt4bj/nwcn a room where the temperature 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 roow-d50l0y rn.wdgnd5x c ;8te wm where the temperature 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 whel96oqimj2 i, an the speed of sound in air is 340 m/s. What is the fundamental frequ2m i oia9ql,6jency?

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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 ope: h1t rxkiv feiw- (gt3eal3pc 8 ,x/;3qlda*zn and the other is closed on one end. If the fundamental frequency of the open pipe is a,ehk*3q l:1 ctr tdvixi -ag(w;le/z8p33xf300 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 freque 3xtkn u 316zw9(i4cbc)sjuer ncy of 800 Hz in air where the velocity of sound is 340 m/s. How much farther back would source 1 have to be m3 kcs x9)crt w j(3i61nuze4buoved 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+ybec3ufl(. gml (as y8nw64y side by side and driven by the same frequency of 500 Hz. (usl(4m ec6.lnyay+ 8wb fg3yIf the distance from a person to one speaker is 5.00 m and the person detects little or no sound, which of the following 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 frequec 2.ja lirr3(2jks fry9.par.ncy?

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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 ta6e oyz d-ip p+dn:76ko tune the frequency of a musical instrument. If the tuner hears a6dka-n 7epo:d z y+ip6 beat frequency of 2 Hz, what is the frequency 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 retzv ly45ro/:dy y)2- stnz 79mj8qaie spectively. What beat frequency is heard wvzq)/:tyi5 sot2nm9lre8-d ay z4y7jhen the horns are sounded on a day when the velocity of sound 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 7wtx+luqi(kq cpze* p :( 1:j5eu4 ztvon two violins in an orchestra are found to produce a beat frequency of 2 Hz:157(t qzx(qe:ujektuwp+ 4 vzlp c*i when a frequency of 660 Hz is played. What percentage change in the tension of one of 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- u8t*vm -3figndx5,wtHz sound source at twice the speed of su *xtn -igt,dm3fwv58ound. 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 (normalmuje (28)x y6dx fon2z frequency of 1000 Hz) approaches a stationary observer at one-half the speed of sod()fo u6m2yn x28zejx und. The 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)ibm:f 8in+/ and6fh d of 1000 Hz. If a listener moves with a speed of 30 m/s away from the sou6:n dnfmf/ba hd+)8ii rce, what is the frequency heard by the observer? (The sound speed is 340 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 is traveling at u2bt top,f5,8 tffzk4p ,c4h: adfx t935 m/s on a day when the speed of sound through air is 340 m/s. The car approaches and passes an observer who is standing along the roadside. What change of frequency does the observerxazf9t2b,c, 4 fop,t5t: t8khpf4udf 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 sji.* l/r dvty)o/ /yh-tj:fcptationary observer when a train approaches with a)t r .pofh/ytivl/j j/: d*-yc speed of 30 m/s. The frequency of the train horn is 600 Hz 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 km/h. The train blows its 400- xr8zm3-vka(.j0q czp Hz whistle. Take the speed of sound to be 340 m/s. Whazqmvak z8j(r 3p-c 0.xt 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 towarqxqw:*jym/b+v bx:, f+f7c st d a stationary train. The train blows its 400-Hz whistle. Take the speed of sound to be 340 m/s. What frequency do you hcxx,bf w7bt:: */vm+f s+ qyjqear?

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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. The train blows its 400-Hz wm838;psx v dexhistle. Take the speed of sound to be 340 m/s. mse88x d ;xpv3 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 at 120 km/h. It blowsp)ixd 4*siclm7xr ; d7lx*e.o its whistle, and you hear a tone of 400 Hz. Take the speed of sound to be 340 m/s. What is the actual frequen s;di**xdi7.)xl l oce r47pmxcy 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 air isieq1oy12v zz 0 340 m/s. What is the frequency heard by an observer if the observer is moving away from the train with a speed of 3z 1ozivq 2y10e0.0 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 h s8d1z.yp1/te x :l t3my5ghirz98kl jorn is 500 Hz. Assume the speed of sound in air is 340ihrde3tj/58zys g.1tx :lkz 1mlyp89 m/s. What is the frequency heard by an observer if the observer 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 p1mk2/yo 31ow2 .c wqwdqpxh/ speed of an object. A 40-kHz signal is sent out, and a 42-kHz signal is returned. Assume the speed of sound is 345 m/s. How fast is the c dyh3po/. 2p2wqw1/1mqkxow 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 produndi88.ko/:ypddifg z,i,oh /9h :enwced by a supersonic aircraft 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 5u zhmk,,q5b5tv bh7sconical shock wz5vhsmb5k ,,7tu5hb qave formed?

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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 United States to Europe with a Mach numbebq4geo qc .tc*si1p;bh*c;.u r of 1.05 where the air teeqhs.io*tq;bcb*; u4gp.1 ccmperature is $5.0 \; ^{\circ}C$. What is the speed of the plane?

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