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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 shrbw3d 3-ne f .s8i -gm(cnp2ktatement?

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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 d)jrxqizi se)8m 3,4v 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 in a stzde17+ h3hmy9 lx2ix zeel 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 happens to the velo)h6i a5kl.-lx)tl 5fjk. j odp:nd1b jcity of sound? (Assume that pllnxhj f1j :id)d 5a)jk -k5tb. o6.lall 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 so xsyd6u(ng5( gund throughungy(6 sxg d5( air 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 Hzpmt g*j;f*k:f sound, the wavelength of a 200 Hz sound in air*tm fk:g* jfp; 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 frequencies greate)4 cow qy ,umrlmmi/.6r 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 freqfq. lx6tb7(1py ;ee q-kh4juvuency 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 directions.6klw2.1widv2,j0k -g sfinnj If you move to a point twice as far away frowi sdj-.klfj2,01 nikn 62vgwm 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 waves, intensity is proportional e br)n:buh2e,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 j8,s5jr;83bn kgr9dsevfqn1a distance d from the source is I. What is the intensity at a distance 2d from the source1e jnn 8r8gd3;rksq 9,5svbfj?

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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 radiatzn8 ksk8pzw 5,3 4vlebing equally in all directions. What hap8zv5eb 43plk8zw ,kns pens 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 from a sound source that is radju k6uw 4ta43kiating equally in all directions. What happens to the intensity level of the sound?uut j4634ak wk 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 8x s5i1ci7eub 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 yn** ljd;l5sqa speaker emitting a pure tone. What characteristic of the sound *jn ;llys*dq5 increases?

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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 musicp0-( bseb ,mucal 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" ofn2v , .oiq;lfa 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 aibhkzc5 ;awd/ 3uj;p2i r 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 displacement wa 5+kwau3ssd: d5- js 1r1opomxt,/lyhves 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 wadvn 5gvr;-0cn ve on a guitar string and the sound wave generated by the guitar a0ngvcn5;d rv -s a result 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 en/wq7mnzc*y* cx /arpo j4o96bds, 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 area qge b 7bc9fp4)gm,9s the wavelengths of the three lowest tones producedbpb 99)fqa7 scmg4 e,g 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 .fsbs +0zwi -.zo zwh9of length L is 200 Hz. Which one of the followin.o.z9 bzf-is sw0z hw+g frequencies 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 np8h4 n;0rcoie,yeqkit:)d 7its fundamental frequency. Which statement is 7: ce8p iqh4;o )ktnridn,y0ecorrect?

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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 closed at thexfx ; qnwh2luh h4j.s ei4(0m1 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. What are the wavelengths of the threr m)ky.syzzcf:ik *+7w90 lzwe lowest tones produced by this pils. w*y7cf9rkzywkz0m:i )+zpe?

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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 ofd(a r:allt 1 g94ihcw+ length L is 200 Hz. Which of the following frequencies will not resonate in that pl 94ha:t(iwcr+ ld1g aipe?

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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 frequ3uu39c8ek (c ps wrj1jency. Which statep9k8 j1 e3c sjru(3cuwment 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 drivllp5i. h mf(k+en by the same source. Each speaker produces a tone with a frequency5phli mk +l(f. of 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 sound wave2e9ysha)w) 3 dmxz/ d(apt1ens 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 frequency i5 r0w,bd wto. m.w1goys heard. What happens to the beat frequency if the frequowb.dmrwt w 51 ,og0.yency of one of the tones 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 explains3 hp:bck(vzy4ecz i:/

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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 hear tg 6,z/q1obwao-2b8cs x8beud by the observobab2-, z8/ w8 tbs 1g6oxqecuer 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 departs from ldx yqep 20 fie;phn3y0h(2 j5a stationary observer. The frequency heard by the obser yxepfj;d2iphheq 30 (5l0 n2yver 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 ) qzi+r gb/paq;y: 6fw49 tdzxwill decrease by a 6+4: )gfptqd ar9wzq;byiz/xfactor 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 ofe ozu nw* 0 *ki eg, ric9y+aip,c6q)zxoe0,e- frequency 45 kHz in air is 352 m/s. What is the air t *- 60a,9 ig+rqy)0 ezi*ownke,cciexuoezp, emperature?

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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 sounnz (m:ywh9 sq:d 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 sp-d(i3 .gg *pi8 axdq: :sqfyyjeed of sound in air is 340 m/s, a bat emits a shriek whose echo reaches it 0.0250 s later. How far away was the object that reflected back the souni8q .d:gfga-y (3s: ijxydq *pd?

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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 heargip7;inwjn1i); ++ plm rj1 ua 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.s. 0tgji.s a.fb 2rvv:0 s after seeing a flash of lightning, the distance to the lightning strikgsfj 2t.0 v.vi r:.bsae 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 temperature isi. huagizw-gh *b0 i8: $15 \; ^{\circ}C$. 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. How , )hb(dcaa m)bdeep is the well? (I,ha)b)am d (bcgnore air resistance, and assume 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 hbst i;c5) -7 x2op)l.bxsvjy 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 at czxh1pn/3p;f$23 \; ^{\circ}C$ 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 intensit fl0w3j8f h g4uf;wt:iw+*yl,iqez 8ey level of 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 ah i2x+xg ib cirs )q(;)yv17kc 70-dB 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 intensities of two sounds with intensity levj; kpy::7 m; jcm2bibeels of 70 dB and 4:bm;i ;:b ypk2je7mjc 0 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 bytx/hw.g n7hf *k 3w 6thbcn*u. 15 engines in a garage is 100 dB. What is the intensity level g6wgbkx3nnh f.c tt/**hh7uw.enerated 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 that is radiating equally in -or.s(2 6ev pia9ky :ohwb6ecall di( aevr sbo 6peyok.cw6: -2i9hrections 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 thatvx+cf f(mg7hj;eg1gs*4 sm9 f is radiating equally in all directigf;1mhj f( scfgv4*g7sex9 + mons 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 ip 6 v;*dqj 9jc/olx(l08hacsys assumed to be uniformly distributed in all directions. What is the intensity level at a distance 5.00 vaj 6 xd*c9;qyphsj8 llo(c/0m 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 atok:ucr4zmw;:cf)v h 5 a distance 5.00 m from a barking dog. What would be the intensity level if two identical dogs very close to each other5:r):c;fw zckmuho 4v 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 ,q r(yj av5-)hdw.5 c0 sa-tqsul;yeksound source the intensity level is 60 dB. What is the intensity level (in dB) at a point 2.0 m from the s( )0-rydqc5e lywhuj -a ,aq;ts5. vksource? Assume that the 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 from a point source is 95 dB. Az( , 1(mdohzoltl x.fzb2y;7st what distance wid(,s tz 2;hmxzflo (b y.zo71lll it be 75 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 iymh6osec2 ,:lwh;;d complex tone has a frequency of 1200 Hz. What is the frequency of the fourdh6 e;;hms,:i wcy2loth 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 kmmh 8xny(t-/g 2aovu8 8 pbl6swn u-4an open pipe is 900 Hz. What is the length8xou2m8sm8ypa-/b - htl4(6nwkuvng 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 leng)4lp/ 3+twillxqnm) v th L is 400 Hz. What is the frequency of th nwtlim 4/)qvx) +3plle 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 ay pz/pu+ 5*ztw69r rtends has a length of 0.80 m. If the velocity of sound in air is 340 m/s, what is the frequency of 65y 9wr ua +/pzt*ptzrthe 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 tempe i,5,mrye i) l6mvxln,rature 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 pipe closed at one end is 330 Hz. tn7 y yj/2;ysg What is the frequency of the third hayy /7t2y ;nsgjrmonic?

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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 close7oh y1o (vz*b67 rlr-pk0vek dd on one end that will have a fundamental frequency of 60 Hz on a day when the velocity of -*d 7e(oov rl6 zr70kbp yhv1ksound 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 i1f ie. wqmg:e;n 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 room wherub 2r 65*k3fw,ftvuige 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 playe+qn)75b bo 4uu rpdib3d when the speed of sound in air is 340 m/sr7nboub i3u54pb q)+d. What is the fundamental 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 lengarhxnf(z k7,3 :uj8 ufzdy -d2th: one is open and the other is closed on one end. If the fundamental frequency of thedzj3:2,ua ffyznh87 u xr d(k- 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 airw dl;zd fi++ - )mjv1mg)pv hvem(9z/b where the velocity 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 szd1dm mvg jv;(9m -iz w+l+f/hb)ve )pound?

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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 frequesv( aept,06 nflf *xtv08n7hqncy 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 persoh6 a,nep qt 08vnf0lsf (xv7t*n 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 H2x ytme8mj + vmt0tn9 d-6y t7dx;5hcwz. What is 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 tb1: kv4+h nu mez2vab.f7;eog o tune the frequency of a musical instrument. If the tuner hears a bezguabvm en4v;21ek hof+.b7: at 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 auqrh ;-s1 /maund 7 m respectively. What beat frequency is heard when the horns are sounded on a day whea1; uqu-m/shr n 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 an orchestra are found to prr . p+,sq)n3h-al tyz2ga.kxwoduce 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 them to the same frequ p t2qanskl+ahy.)xgw3 -,.r zency?

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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 statioh c tbi(qr42.y/x;m ktnary 1000-Hz sound source at twice the speed of soun . 2(ihrqtct4x;k/mybd. 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 frequen9 z 1 ;-ktrektmm6bq;gcy of 1000 Hz) approaches a stationary observer at one-half t;mz;et -krm1 kb96tqg he 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 1000 Hz. If a listener moves we.7.ircj 3ety9qs1cruk v63 zjn+f9 fith a speed of 30 m/s away from the source, what is the frequency heard by the observer? (The sound qr t.1uc397e+9 jj6sfy frcivkzen3. 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 traveliptve 1doi0uc8 7sc4so8w-z g.ng at 35 m/s on a day when the speed of sound through air is 340 m/s. The car approaches a81io7tesocw 4 d p z80-sgu.cvnd 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 observ(s ;q.mwdrr j/f 6ged)er when a train approaches with a sp(d q.gsr w;6dr)fm/jeeed 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 it vk97c 2hh9qi aw)5jjfs 400-Hz whistle. Take the speed of sound to becjj99fw5h 2 av7h) kiq 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 m+7+(z yo*abx1o h cg*z)kdrhtrain. The train blows its 400-Hz whistle. Take the speed of sound to be 340 m/s. What frequency*+bkh(orhym z )+ca1 z*ox7gd 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 90n6ffyk (dpp dg.7 ea120 km/h. The train blows its 400-Hz whistldd 90n.p7( fekp gfya6e. 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 km/h,l-lb xp;s t)j. It blows its whistle, and you hear a tone of 4lb;-spj xl, )t00 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. Assume the kci96xwjxt s7k;y8u ;speed of sound in air is 340 m/s. What is the frequency heard by an ob9tic76kyx;u;j w8 ksx server if the 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 horn is 500 Hz. Assume the speed of sogzpf0ana h 8 c1sl/z+a(x1i0sund in air is 340 m/s. What is the frequency heard by an observer if the observer is approaching the train with a spe 0scfzgainpx1al+(/s 1ha 8z0 ed 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 objectw( d1s tp9ssn8. A 40-kHz signal is sent out, and a 42-kHz signal is returned. Ad8st swns1 9p(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 aircraft is wplrk)35 qrnnh .,/dvjt8 y,o$60^{\circ}$. 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 ofrdj i4z3f)hud)fa sc9l5i/- l the conical shock wave foa /f4l sl f9dh)zi5i j)r3-cudrmed?

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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 Unitedcun/mc).hrnf tch 0sfz( :07znutdf 7o2q ,y4 States to Europe with a Mach number of 1.05 where theq 7h2mcz fuot.nny47 d0c/ fu )(rt,fcn:0shz air temperature is $5.0 \; ^{\circ}C$. What is the speed of the plane?

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