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习题练习：Physics Unit12: Sound
本习题练习来源于51fly国际课程 (https://51fly.win)，是在线习题练习的打印版，您也可以访问本平台网站(https://51fly.win/)直接在线完成(注册并登录账号后在首页左侧输入试卷号 70 即可在线作答)，，作答电子化后可随时回放，查看每题答案与详细解析，搜藏保存任意题目；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。本试卷的直接作答链接 https://51fly.win/test70.html
 作者: physics  发布日期: 2022-09-26 09:56    总分: 87分  得分: _____________

答题人: 匿名未登录  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 fchmum07mipz9sk bb-v8(o; t:alse 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,5pq ksw9z;xcyo4fg , 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 ishqk34w7y zj; n 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 a*9aat;,8swc5zh f eznir increases, what happens to the velocity of sound? a5;9 tzazn* fwe8sch,(Assume 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, tix14zwia9z c9od -u4she velocity of a 200 Hz sound througdwuz9ai o1- 44cxis9zh 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 /x5kk sv8z;rh8:sih eof a 400 Hz sound, the wavelength of a 200 Hz sound in airx:z ;85h/8vssik rkhe 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 frequencieovmo8 xfm ,.3o(r1nor s 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 tocz dyc -tt0c-8zf ;h0han 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. srpp +n v ne l17tp+3ss;63q.bw8zc acIf you move to a 3sc.pv6t+ 3r abe nw78zp scp;q1+snl 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 diverging waves,4pke12ea/nhhtrb * 7cz bi,;d 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 dc1lkf ,n o u- 9hb,9wq+ ruex)xhd/l2i from the source is I. What is the intensity at a distance 2d1eo iuxb+,-9chd 9xhu2ql,n )wlf/ kr 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 radir*0xknn lha9esi(d/ .ating equally in all directionsn.x ki9*0asn (he dr/l. 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 -k:bwbkej14 s from a sound source that is radiating equally in all directions. What happens to the intensity ls1 b:wk4e -kbjevel 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 0c.oiaiy0h+u39q0uo s3h kcw 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. Whasym/x6 id3i7 jt characteristic of the sound insj/ 3ixm 6dy7icreases?

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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 cw 0 uwk6cbkguf25ztf g1)b.8note?

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17#
 
单选题 ( 1.0 分) 切至整卷模式 搜藏此题  
  What determines the "pitc3ctvlqxcs + sgu, i:a l) io.5ms5k7.ah" 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 watji0j z 2ri h /hp;7h:rbtl,m*uer

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19#
 
单选题 ( 1.0 分) 切至整卷模式 搜藏此题  
  Pressure and displacemengf6r/ 4cjh v,j+awg 7ot 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 wave generatd6rqu)rt*a 3s ed by the guitar as a result of this vibration. t r6da*rqus 3)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 whicokn 5kr )imf i*m-v2j ih,9.hah is open at both 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., ftq jq(q g/2rwy*t4 sd1 b3c6ziby,q What are the wavelengths of the three lowest tones produced b r qy* t,j(d 2,wcq3iz4ytq/bbf6s1 qgy 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 -veit03 ikc6gHz. Which one of the following frequencies will not resonate itv- 0ei6igck3n 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 fr0s:1kf37owdrkjd c/ l equency. Which statement is correct? kdks 70/:rlcdow f31j

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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 n81o-xqd gbd9 jq-w;ais open 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 length L. What are tsysrgb22t;v 1 he wavelengths of the three lowest tones producbg2v sst ;12yred 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-d w pf8vm8gg- Hz. Which of the follo8 gpm--fg8w vdwing 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 frequefk w6k(.bzfyv/c ,.n+:hi pxdncy. Whic6hi.b+vx,(kzyd fn w . ckf:/ph 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 drievxt8 +z*r/3mj rnq5b4w 1hftven by the same source. Each speaker produces a tone with a frequency of 200 Hz*mr w zh8f4txnr tv/ 3qj1+be5 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, t ( ht* ujbwoxz0q;zbcr8y sq;xe0/ o51he 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 particul:psojm6h) fz ;ar beat frequency is heard. What happens to t: zsf6h)mo; pjhe beat frequency if the frequency 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 expl -. /,;j yuu2 j.dfftgehqytw2ains

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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.7(mmc u iv+btd by the obsim.(u+vm b7cterver 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 fro*1*/sbr ucwm pm a stationary observer. The frequency heard by the obs srup/*w 1b*mcerver 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 do;hvz ,cqjs4sz4v05z4s lq4eouble its MACH-speed, its half-angle will decrease by a factozcsh,v4oj;5z z sle4qvs40q 4r 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 freq/ ok 8s)r(zykyuency 45 kHz in air is 352 m/s. What is the air tekys/z)k8(ry omperature?

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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 spezc9.m3 dve n*ied 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 i kb*7r.ozyn 0zn air is 340 m/s, a bat emits a shriek whose echo reacyk0. *zznorb7hes it 0.0250 s later. How 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 s0qo 1gh ntn)mc1lqm 33. 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 lightning014*puv rbzwabk t8 /n, the distance to the lightning strikn8p/10buvr t kazbw *4e 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 onqa mlb-z;d :hzk1. ji4hoa.b 5 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 at,q6zi d s5pb5nd hear the splash 2.5 s later. How deep is the wellps6dqb5t ,zi 5? (Ignore 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 500 Hz nt ;8kx8ne(k2 hberr1 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 airo;58 gnbbwq 3a 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 6p4ktihm.j8a 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 sounde.u 0 hgvi.bk-?

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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 z; 27bl9kk0p kve. bmffrs6 x,sounds with intensity levels of 70 dB k07evx9l f,bp;mzbkr2sf 6k. 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 insn- hzdq-tbh* w p *9tz1f-d6s 100 dB. What is the intensity level g *dn*-p196-s bhhttzdq-nw zfenerated 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 frtpr7gv3v h8fmd:0zzt*z6qt 8om a source that is radiating equally in all directions is803hp6z7ztvd t tfm:grzv8* q
$6.0 \times 10^{-10} \; W/m^{2}$. 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 :ho-mlgka -o ,l.b o:/bxuldd*;ro(h m from a source that is radiating equally in all km- hb(dob/-.ol* u:h:gol,ra d xl;odirections 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 61wt5y yh)s 8,8qihx5uvrmkbof power, which is assumed to be uniformly distributed in all directions. What is the intensity level at qy6m5hhsit 51u,8)rb x vk8wya 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 au a/hj:ty0mb )t a distance 5.00 m from a barking dog. What would be the intensity level if two identbj/mh0 :uayt)ical 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 3rdb xl6.nrwn9ok/ ir9a69 p .dmibe1 dB. What isnbr dmd.6 1b 6x i9lw3/rpnei9rok.9a the intensity level (in dB) at a point 2.0 m from the source? 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. At what distanceu2) q9vs0mji )rtvu7w will it bemw0ivru) su27vq ) j9t 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 complex tone has a frequency of 1200 Hz. What isats3q qzm5gm,7u+s9 g the frequency,qgsgz5q9mtma 73+ us 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. W68vgr z2ran( dr251iixh ; etthat is the length of the pipe?;2gtt(6hzevxid82nar r i r51

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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;*m b5cier+f xddd2x 0zl.de7 of length L is 400 Hz. What is the frequency of the lo5;m+cr7ezxd 0i2x*fe. dddl bwest 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 velocity of soc jhfrt 52w 4) h1e13bq+bvwlpund in air is 340 m/s, what is the frequenc+ljwbf25 whc3v rpb1eq)h 4 1ty 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 temega/,bs g) -fmt5xtj9 perature 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 z7 1m0rhxeu9 v5)d:l wud,mfsone end is 330 Hz. What is the frequ )1,ldvhw fx9 m5u:7zrdmu0seency 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 9b8d 42nc kgrn zous+6pipe closed on one end that will have a fundamental frequency of 60 Hz on a day when the vegrun zb n9kd+628c4s olocity 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+xb lg+ru7 hy h*9tni2 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 w+owlvtpu0 9n9+ o.2xvria b (7 odlpz5here 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 lezm f,n;92h 2ntjc vr3y8,trs )lppgq;ngth 0.75 m is played when the speed of sound in air is 340 m/s. What is the fundamental frp nm ,,3jrcft zp8t lg2qs;vn); 92yhrequency?

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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 same2( wza9vo1a dwgqgz y +8*n-pe length: one 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 frequency of the closed pipw1(o8 q*n+w 9g a-agvyezp2d ze?

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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 fr r;f3p );joeij3s+web( b.a bkequency of 800 Hz in air 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 sfb jbi;ep(o) ;3k.j3sa er+b wound?

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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 siv4 :90daxdh1xs35h :6ylz-zasaob v3armf3bde and driven by 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 following is a possible the distance from the person to the other speaker? (The sound speed is 340lams36y x0bavhbd 1s d :-a :3vxhz3r5a 4fz9o 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 frequenciesle y z24q/vgy7qr-c 4,xqvk3b of 440 Hz and 444 Hz. 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 to tune the rytiq8lhab n*)nq z 0(y;51xrfrequency of a musical instrument. If the tuner hears a beat frequency of 2 H0 r 8nlz5xy(hy b;q nti1a)*rqz, 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 mdyuqc9r z4, (k respectively. What beat frequency ry9(kcd4,zq u 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 an orchestra art)mtfbz)5bn +e found to produce a beat frequency of 2 Hz when anf)tb)m t5 +zb 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 100zu/7se/2b x ti0-Hz sound source at twice the speed of sound. The observ27uez/xsb / tier 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 ze*1g0acw0 d cHz) approaches a stationary observer at one-half the speed of sound. The observer hears a frequency ofwc0g adc e10z*

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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 6 u( zadiiw tn+0mr+o+oq .uges2+h g6Hz. If a listener moves with a speed of 30 m/s away from the source, what is the frequency heard by the obsenw r (deu m2iqhgi6o6++tgu 0a++o.szrver? (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. Ifz 3 5rtb,8yhe w8si ,nh7pu,nt is traveling at 35 m/s on a day when the spe3, ei,hyhnp usrn 85wbf87t z,ed 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 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 ap)mc0. ju 7a 6rpp:te9 vtjc+twproaches with a speed of 30 m/s. The frequency of the train horn is 600twv m)cp+60a 9p u.ej7tcr:t j 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 zw1ud7 g+be- bf3in7pyou at 120 km/h. The train blows its 400-Hz whistle. Take the speed of sound w+fiud np-e7b bz3g17 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 blowd4* fh b6b2.glypxa:as its 400-Hz whistle. Take the speed of sound to be 34b:42b.y p6hg fa* xald0 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 train blows its 400-Hsvj4v7 php(svey 6w70z whistl7y67j 4svs v0 (eppwvhe. 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 at4gsikf r./rum lwu:izz.ye+2 8f2i9 s 120 km/h. It blows its whistle, and you hear a tone of 400 Hz. Taiu su zif2wzk9ms.:i/lg8+fr y24 .r eke 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 ur +pba*rj (y4is 500 Hz. Assume the speed of sound in air is 340 m/s. What is the frequency heard by an obser *4 jupay+rb(rver 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 sound in h-or u9d xm ,5:qbxjm-air is 340r5 -dmmobqh, :x9-jux 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 speed of an object. A 40-kHz signal is xb; r2cdragx 3-+u4vqava 9nr*pe4 f4 sent out, and a 42-kHz signal is returned. Assume the speed of sound nv4 cr ;*rgx4ud4fa3aaqe bx-r9p v +2is 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 conical9iyd re+qe.h* ed/xwj i192,4j wlxlu shock wave produced 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 conicynf0ws 7:b5l g1vx4 +unfcg5y al shock wave forme1ufvgnxwyfnc b+ 7g 5y :sl540d?

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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 Unp;31vgq/4o iawi4hml0 td ntg2wui, +ited States to Europe with a Mach number of4diw 1ivgu/tm;q4tg3o pn ,l+whi2a 0 1.05 where the air temperature is $5.0 \; ^{\circ}C$. What is the speed of the plane?

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