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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 false sta 8 cqt 4s6qh+rmri+/m*y l5vzxtement?

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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 conducug jkn81 t(ki(ke9 bb)ted 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 sound inn xb*5dlh:l52ffd qh+ sn:hq 7 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 of the air increases, what hstx, u6.pq1c eappens to the velocity of sound? (Assume that all other factors rem6,se xp 1c.tuqain 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 velocitymj: r)rtq:x3l of a 200 Hz sound through aqr):rjlx3:m tir 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 Hc,b xsn w*6nkf1 1blp(z sound, the wavelength of a 200 Hz sound in afxc*psn16 b(k1lnwb, ir 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 frequ;vp2w3mrq.r z0m41eh2x*0clso scs aencies 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 2lb.5 a.+msx yc0 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 w*fm7ud7l64w4shzbhf3 y qi zcy7+zw+aves uniformly in all directions. If you move to 7f 34*yui+y 7zmdszwz7 h 6bf4c h+qlwa point 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 diverjyg7;x;o) 8euqx xkv ,ging waves, 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 dizh-/)kxqcbfp4d9 5hzstance d from the source is I. What is the intensi c/9k4bpz5h h)q-xz fdty at a distance 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 dista9gl/wo8:;*-7 yl djehu dsrwwnce from a sound source that is radiating equally in all directions. What happens to the intensity of the sound? It reduu7 :;-w/ hwjy*le9 dsdwlog8rces 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 equally in a t7au5ihiyv/,ll directions. What happens to the intensity level of the so7ahiu v,ty5i/ und? 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 increas*mdgh v i(w9j)es as a sound 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 characterx 3 q zxybg;+p2..7gy,e5 ;axb lxfuctistic of the sound itx x; q 7upzyl.ae+ b3gc2;f,yxb5xg. ncreases?

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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 musical notufe,bwn 8 )nz7e?

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17#
 
单选题 ( 1.0 分) 切至整卷模式 搜藏此题  
  What determines the "pitchmhr g );1r31tk:xnx to" of 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 air into wblzbgn /po .utnq ist4p i:5;x;0 (b7cater

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19#
 
单选题 ( 1.0 分) 切至整卷模式 搜藏此题  
  Pressure and displacemea- mf614pz) :hkp xx z)wphgf-z(uev,nt 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 guitar3 cn6r anci:p;h.amj8 string and the sound wave generated by the guitar as a result of this vib a3 .pmr6hnac ;8nicj:ration. 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, ther fe4xodq)z +e c;qep1: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 length L. What are the wjq+mb *t4jcq5g4m6o zavelengths of the three lowest tones produced by thisb*mtm j+j4zq56 cqg4o pipe?

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本习题练习题目来源于51fly国际课程 (https://51fly.win)，学生可刷题练习，扫右侧二维码或加微信skysky1258，获取更多资料
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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 onz:0 0kjwgyr -de of the following fredgk-0:wr0 yj zquencies 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 itsl,nw9 fmxu; 8p fundamental frequency. Which statement is correp xnl,8;m9 wfuct?

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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 at5t;ia hpfxgozy ,:2w)o0bl4q 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 lengthmr h+2:s+f lqpkqs /i/ L. What are the wavelengths of the three lowest tones produced by this piprq/+ +mihl ks f:q2sp/e?

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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 r )3ar.dceol +tqedx,8+ d u1qpipe of length L is 200 Hz. Which of the fol1+e)q ru.atlq r,cde o3dd+8x lowing frequencies 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 frequenja6c cb;b)(5bl(yb7uiu+ yd yba 3yy0;3ucrccy. Which statement is cy u ybub3jda ;ic;a 6(5b y3()urc7lcycb+0yborrect?

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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. Each spe (n s gnmz;0:zb4xhg1m6/suh* bvm8ypaker produces a tone with a frequency ofxgh/:gnshz *b y6 mnm041bzs8 m vup;( 200 Hz on a day when the speed of sound is 330 m/s. The 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 beats, the two sou6q+y w3ups knav )y2x6nd 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 andh* net k-9g.o,2umdqx a particular beat frequency is heard. What happens to the beat frequency if the frequency of one of the tones is nqed. mtx 2 ,uo-hk*9gincreased?

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32#
 
单选题 ( 1.0 分) 切至整卷模式 搜藏此题  
  The Doppler shift explains8*rmxqoypt:70 ql+r ni.3e * tm n.wof

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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 stationary observer. The frequency 012jd/xvysgyyaj* v - nk0t9wheard by the obs/ jv0w*kaynd yxj gtys129v0- erver 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 depart 2wavc,xcmkmr dqah2tn-3 c h-l73d/-s from a stationary observer. The frequency heard by the obser3l k -hhmxw--m3 q/vtnc,rcd a722a cdver 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-angle will decrease by a uroj7/jd7n /u u6+rzsn p6hc9 factouz7c hj 6drru7n6 j+sp/uo/ 9nr 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 45 kHzx2a uer/djr r6( e809(du yufe in air is 352 m/s. What is the air temperf02r9erejrud (uya6(d /8ue xature?

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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 spepv a3dc6.bf2 sed 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/ ,5b0jr j,gdems, a bat emits a shriek whose echo reaches it 0.0250 s later. H0 b,d5gj,mre jow 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 the echo in 4.00 sw.ng-vx d r4n: gq16chx+ f1hx. 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 ii 4c r8:d umsrf6ob(0of lightning, the distance to the lightniscf( d:u 0o4rmrbi86 ing 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 +u wxh2z1tu ..hvxib( from a cliff on a day the 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 andrds4gerv 43u6 hear the splash 2.5 s later. How deep is the well? (Ignore air resistance, and assume the velocity of sound is 340 m/s4sr ge46d3uvr .)

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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 frequenh q ud:kpe-jo b;+dazv, *3cyjh)k2o( cy 500 Hz 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 air bjtwhd);8, aif mce65 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 of a sound with intensi 66 vc7twpsr6oty $10^{-3} \; W/m^{2}$?

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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 sodz e3/2miub -hund?

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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 sounds with intensity levels of mm3+2f5kicwq3x qk8d70 dB k332 kiw +xqq85fmmd cand 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 ik2 zfl (,,ic y.ixt*j100 dB. What is the intensity level generatedfckyzx,(ti2i *lji., 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 thnwh0r. 46unvlat is radiating equally in aln40.lrnu v wh6l directions 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 fry ejsofs7j +5zc+p) f8om a source that is radiating equally in fs+ jy57jzfs)ep +8 ocall directions 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 nu0 +/v z (vxhjxpfw7u2 e8e;q1 mW of power, which is assumed to be uniformly distributevn zefuehxjpxvu;(+q78w0 2 /d 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 from a barkingqt :*4;m cnmfe dog. What would be the intensi mt 4fen*c;qm:ty 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 level is 60 dB. Whatd+ :2-xgyk;yjtk myb9)7tev l is the intensity level (in dB) at a point 2.0 m from the source? Assume that the sourc9y-kjt)7kx;d2y+lbgm tv : e ye 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 from a point source is 95 dB. (ztdqs q wqat931t,:i At what distance will it be 7t1t (twas:3,9qq qzdi5 dB?

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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 the4p:ml0 2ybimko j:7 42(r0lyltvk yxd frx720mdo04y y ltljm(ky 4 p:bv i:rlk2equency 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. Whabby7 *n8fu vz-t is the lengthz*vyb -7fun8b of 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. b 9f1g nmjhbm3gxv pgo)vc8-;rg:ygak/:n5* What is the frequency of the lowest tone that will resonate in an open pipe of lengta-g 3n/g1opkm :g;xbr*yhf)v5:8mb ggn9jvc h 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;rcpe(n4o6yg ends has a length of 0.80 m. If the velocity of sound in air is 34g;p yo 6(4ncre0 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 the temp i x(wp7o2 an:+wnve,ferature 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 in a e iipciu+m*b:6d+ p2m pipe closed at one end is 330 Hz. What is the frequenmm+ ei+i:cu bpd26* picy of the third 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 the shortest pipe closed on one end )idiv7 mf* xd3that will have a fundamental frequency 3vdxii7 f)d* mof 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 tempeyps1t)1 ee54sj nz k*nrature 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 temperature is+duxhmcjja5wl *48c j oa6 a+h-fj w,* $20 \; ^{\circ}C$. 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 spee g dqe +kcg0,0mu(po.qd of sound in air is 340 m/s. What is the funda qogc(u,0md+q0kg. ep mental 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: o3lc8mlqk 3:b sne is open and the other is closed on one end. If the fundamental frequency of the open pipe is 300 Hz, what is the fundamental frequk3sl3c8 q :mblency 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 ,8xn1xb+ab gcvelocity of sound is 340 m/s. How much farther back would source 1 have to be moved so an observer in front of the sources would hear no n1+axb ,x8bc gsound?

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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 by the same frefs*l1l 5wi w5i.cq +wbu47 cucquency 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 following is a possible the distance from the person to the other speaker? (Thucc.l lw 5wsfwbcii u5*471q +e 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 i n(1cy;ammx2 t 2ix,pxs the beat frequency?

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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 frequency of lyoi8d30v ,qeexwq0 w* fe;h 2a musical instrument. If the tuner hears a beat frequeo 3 f,0wh*qevweldx;eiyq8 20 ncy 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 producehsw4b,c n rhs* ews(xa (-0y:xd by two horns are 6 m and 7 m respectively.-(w( 4ears0 hxy*:s cwnh xs,b What beat frequency is heard when 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 on two violins in y0 s;lkkxw1 7a4y3 fdgan orchestra are 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 of the strings would bring they;ak4l1s3y gwx7 fdk0m 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 stationary6 sm;u yqnd2(w 1000-Hz sound source at twice the speed of sound. q6s m(2yunw; dThe 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 stationary o9zj2zzzzx 0z qmzv bf*-0r 3q/bserver at one-hz9zz0*2z03/qjrxqzz z bf-mvalf the speed of sound. 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 of 1 .u6 a;qgabiz-000 Hz. If a listener moves with a speed of 30 m/s away from the source, what is the frequency heard by the observer? (The sound speed uibaa.zg;q -6is 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 trav 6(e7m l3clgdnr./m apeling at 35 m/s on a day when the speed of sound through air is 340 m/s. The car approachelm.l(e3 m7dcnap/6r g s 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 stationary observer when a train appgjiew,k6 uq 4e5; mqc7roaches with a speed of 30 m/s. The frequewiqkj ce6 5uq e;,7mg4ncy 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-Hz whi(u ue(f 3) slgq8dl-wjstle. Takulq )3-lsefwd(gju(8 e the speed of sound to be 340 m/s. What 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 stationary train. The train blw-8eplo0v exey8u2e 4 */e kluows its 400-Hz whistle. Take 8ekve 0-8e4x /*pel2 leu oywuthe speed of sound to be 340 m/s. What frequency 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. The tro+ow- .tgl 6kaain blows its 400-Hz whisk -o+ towl6ga.tle. 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 at 120 kq xatfg(8o e h*d4 f20rmaqz6mn8y ),am/h. It blows its whistle, and you hear a fymaq286ha mxge 0qzf8an) *,4ro( dttone of 400 Hz. Take the speed of sound to be 340 m/s. What is the actual frequency 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. Aspa .-.gufg3wz sume the speed of sound in air is 340 m/s. What is the frequency heard by an observer if the observerwuz g3 ..-gfap 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 horn is 5nu2)yj67ln m.kj0 f1wwza g/ k00 Hz. Assume the speed of sound in air is 340 m/s. What is the frequency heard by an obsefw 7kj6 ky)1n/ 20wm.gnjzl aurver 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 determi) q14vyl3ydhn, rl, mtne the speed of an object. A 40-kHz signal is sent out, and a 42-kHz signal is returned. Assume the spe r)lqt,ly41y nd3v,hmed 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 aircraft am r-ay 9eu eq4m*r.9a3we /fdis $60^{\circ}$. 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 orj-o .tw2) lymee+u f)f Mach 1.4. What is the half-angle of the conical shock wave jm-feu+l)oy e r2tw.)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 witm krbovkc: j9n6. nmw7n +f27wh a Mach number of 1.05 n2:.fw7+6cn v n kmkm7 rowb9jwhere the air temperature is $5.0 \; ^{\circ}C$. What is the speed of the plane?

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