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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 following is a false statemsrfji*;q nb9f( j) gj07fg3x aent?

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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 coh :rz92hynnjl6v 369qum2* mjuhonc8 nducted 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 sou 5o 6 irwty+bl,sqm /q)t dn,ix.;;nd;wfcuh,nd 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 o,zrjr zru:ci,y-pc16cw g(6 jf the air increases, what happens to the velocity of sound? (Assume that all other fac,(jc,ur wrg 1 zyi pjc:6crz6-tors 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 sound thr2mxy5u*o- lgj+ohg ,houg+u o,2hgx-l *m5gyho jh 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 Hz stupzv7x 8y 5f0ound, the wavelength of a 200 Hz sound in air izvufx5ty 7p08 s

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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 greatxjl m+)bi z cnca5w+*0er 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 callemc 00fg9:angpd

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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 isu; ug derh5/f8 emitting waves uniformly in all directions. If you move to a point twice as far away from the sodu/g rh5u8 ef;urce, 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 d(9 1l)qujzyd 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 iwk8yvh*)h x 7ys the intensity at a distance 2d from the*x w7) yvhykh8 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 radiaq /wxt,j5 z0cr7tk6tgting equally in all directions. What happens to the intensity of the , q6k/t07rczgxwj5ttsound? 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 z8pl, t9bl2 z13ogqhb a sound source that is radiating equally in all dire3 z8phb lg21tqb 9o,zlctions. What happens 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 sound h*w;im vb)n wpulg,6 9becomes 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 emittin5+ta5y q 8julsa/f 1hgg a pure tone. What characteristic of the u gh1y q/+ 5s5latj8afsound 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 musical nx5x gb8hy:zu 6;/xj1ai viou( ote?

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17#
 
单选题 ( 1.0 分) 切至整卷模式 搜藏此题  
  What determines the "q lw pm*v+y7 f.-:rtkqpitch" 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 frss,( zi b/c qa/i3txw.om 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 displacement wakpp (/ 5xjg; kzwixs)r40lq e7ves 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 a h trf6g4xg-3ojaal* (xh;/v on a guitar string and the sound wave generated by the guit/grjh*a-t(4f3v xah 6;lx agoar as 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 ends, therey l,:iaj 0pv9y

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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 tzsk fi; k324kwhe wavelengths of the three lowest tones produced by this pipe?;sfzki3kw2 4k

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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. Whicha xmgp-- mio,i ozx)*3 one of the follo,z3 *i-oomg)m-aix xpwing 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 its fundamental f mprgt 0g14;karequency. Which stat g0a1 ;r4tpkmgement 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 andecrn g6ja9blm )a.p0/ 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 tb yzvyz/krz1+ ;l1 3rop h ps1se4v0b*he wavelengths of the three lowest tones prod+1 yvopbhes z r/1y*zv0kbz34s1;l rpuced 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 clos5gv,zt 5qes n/ed pipe of length L is 200 Hz. Which of the following frequenciesst , ng5qez5v/ 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 resonatinv a :-2firas3vg at its fundamental frequency. W3r 2ai- af:vsvhich 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. Each speaker p,*aqm r-9mi8 pyufl:xroduces a tone with a frequency of 200 Hz on a day when the speed of sound is 330 9qy-x*fl m8a,r mi:upm/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 s17fn qy7qj *7*wrwbvo x w3mmhy d2+.vound 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 toget7 f7j8oh)scboher and a particular beat frequency is heard. What happens to the beasj7ob8 f7 oc)ht 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 explatyql98 :x vxu4ins

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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 frequenpazjs-uef kcx1ss77+3mr;(t( r /ztpcy heard by the obse;rxa p7r/cu-+(7mkt t jespzfzs1(s3rver 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 a sto /f1lag*3 / mbaqvwt/o-/fmm ationary observer. The frequency heard by the observe t*la1 qa fmmv w/obg/-o/mf3/r 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 k4i*:uo ed j8dt2y.q+jn/hhs-angle will decrease by a facto2 t eq8 dj:si+jhdh/*4yu k.onr 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 kHz in air iu 5)adgvjr:,6 ih0eyns 352 m/s. What is thjuiveyr, )g h50d :n6ae air temperature?

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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 air auu-n :/,,.i v7wcuij0s w clhlt $0 \; ^{\circ}C$ 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 zy,(ve :z3s tebwg+0sof 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:sg0(,sz +z 3ytwebev 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 ecyff+ev uuxs 50z90nc 7sfs 90nho 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 syf t )k13 etpq2w8fj/u f:ybz8eeing a flash of lightning, the distance to the lightning ut2fkf3w 8p /fyjty:8 e)bzq1strike 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 is c,3ukk5lv v g2$15 \; ^{\circ}C$. 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 ww08t,6 ;ze 6ip 1*rfvzjbzdrbell and hear the splash 2.5 s later. How deep is the well? (Ignore air resistance, and assumj wbr0z,e 6t8vid;p6fz b 1rz*e 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 itwnmb n08. :k. );pqy zaz)gpof frequency 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 asi8k e,no. -twt $23 \; ^{\circ}C$ 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 intensix e98lxf91jno:/ g.qvlrq1 hkty $10^{-3} \; W/m^{2}$?

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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 sounyi 8-v2d +nv o)j7n3ywu*ldc,hw5c ehd?

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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 inten fetd9p(9ex21 mc8dyp sities of two sounds with intensity levels of 70 dB and 40 d1 yem e2dt9dpp8fcx9(B?

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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. .q8 sxcgk/6 *meo o-fwWhat is the intensity level genog68cq* fx- /ke sow.merated 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 ey:m-7*k: pd557, nkdry* ghmaqewberadiating equally in all directio*yk*:b-e5ehd77wdgmeyk r m ,q p:n5a 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)vz) fc:ozggkw5i 4 b1pu3 hm* source that is radiating equally in alpk 4:vo5g)c1fwi3gm hzb)uz *l 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 1 mW of power, which is assumed to beq nz5+x 1f6m z11jqx rwo;oe6w uniformly distributed in all directions. What is t1oxw 66;m1w 1o 5fn+zrejqqxz he 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 f fkv2gk;(hq *utkt2lk 0b/2 mcrom a barking dog. What would be thk;k *q tcfb(uhmvgk2 2/tlk 20e 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 level is eo zg9 x9pgl 3jlqu(,(60 dB. What is thj,gq9x u3(gpelo9(z l e 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 sou)ao/nc)oyp- lrce is 95 dB. At what distance will it bnpaoy- ))c/ ole 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;g3 t7blglp9oh,n i 6y. What is the frequency of the fourth hll ogpy 7b9igt ;n6,h3armonic?

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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(37oiricxao9f36 6p ww. uoku an open pipe is 900 Hz. What is the length of c37x( iuio wakr3u.fop696wothe 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 op 8yg shex1s+. i(.06x ibqxurben pipe of length L is 400 Hz. What is the frequency of the lowest ths1bxrgxbqeiu s(.+y68 i . x0one 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 the0d w+esec;zc, velocity of sound in air is 340 m/s, what is thez;w+ csd, 0cee 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 temperafc05i p i+6iwgture 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. What is tu3 ,yao vs ai58h;z4qyhe frequency of the third5q,his y348u;ayv zao 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 onm 1skxb rg/)p3w na2uqw:-gj0e end that will have a fundamepqr:n2) / 3u10xk-g samwwgjbntal frequency 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 temperatue9w4 /ossv ;3b8yqscv re 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 3ip4 d8ry9il. p5htnxin a room 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-;packq9x;g+fhdwsa i:4j j. 0.75 m is played when the speed of sound in air is 340 m/;9dc4.wj;-g q k:ajsi fpaxh+ s. 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 length: one is open and the other is clo*teveac4qvn5 1vced-m m1y )wh8* 2 hjsed on one end. If the fundamental frequency of the open pipe is 300 Hz, what is them jvt*a 11qv 4ewdye -nc2hem*v)hc58 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 velocvj+y fb;owl--fa l7o;vhv-xic hj4 , 0ity of sound is 340 m/s. How much farther back would source 1 have to be moflbvi-jhlv+;4, -o - vhwxa c0o7;yfjved 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 siyf i8,gleejte2c 0)7 wde 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 isy fi 02l8w e7tegj)c,e 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 x 1;:e7 qjgd:o,fjnko 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 55 h7gva 8cu2a;p4e(vegoumx (30-Hz tuning fork to tune the frequency of a musical instrument. If the tuner hears a beat frequency of 2 Hz, what iauvp 3evh ma;c2xe(o gg 74u8(s 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 soun1kn upydzjdm57 y .(z-ds produced by two horns are 6 m and 7 m respectively. What beat frequency is heard when the horns are zj(nydm 5z1y7-kpdu. 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 vioq ck)o+hm tsr9h4hh-/ l)fm+clin strings on two violins in an orchestra are found to produce a beat frequency of 2 m kqm9sohfr h) hh)lc++t-c /4Hz 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 10tq0ren8rqm v i( hav)6*qy/p1 00-Hz sound source at twice the speed of sound. i0 v)mqp*q 6r8(navt/yqhe1rThe 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 observe gq*+q) /;olw;zna5t c7xzuud r at one-half the speed of sound. The observer hw z+tq; nu* l5zcx/ao gq;)7udears 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 mbz6u+4p0 cifk/z6 6 wfka 7hbHz. If a listener moves with a speed of 30 m/s away from the source, what is thp70fzw ufibah4 /c6z66 kkm+be 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 35 m/s on a sju8tbnoy*2 wa*+i6jadf** tday 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 nj6j*2dsf8o +wy ib*a *t*tuaobserver 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.uy yp qjf2:o* heard by a stationary observer when a train approaches with a speed of 30 m/s. The frequency of the train horn is 600 Hz2 .fo* :yyqpju 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 bu:9ed,pw5 sv ilows its 400-Hz whistle. Take the speed of sound to be 340 m/s. What fr pd w5,9vse:uiequency 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 sta0css1 d(*e mc)7/p kjecs8zdntionary train. The train blows its 400-Hz whistle. Take the speed of sound to be 340 c/ 18sd7 mc (zc*ese0)pjkdnsm/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 atqnu )*u)b3y rn 120 km/h. The train blows its 400-Hz whistle. u)ry3bn uq)n * 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. It blows its whistle, 4qnto8 +mdo +eand you hear a tone of 400 Hz. Take the speed of sound to be 34 + oqnmd+to84e0 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 th(* pcm,c ifitm1g4lr3e speed of sound in air is 340 m/s. What is the fr* 1plmg3,4(f c itimrcequency heard by an observer 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. o1bqw:k o f: ):nmd,ofAssume the speed of sound in air is 340 m/s. What is the frequency heard by an observer if the observer i1 dnow,o:f qk:)fo: bms 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 speeg15d0vjzd07gyr kx;,ve sc o:d of an object. A 40-kHz signal is sent out, and a 42-kHz signal is returnv 70j5;0: 1 gsgxkyodedvrc ,zed. Assume 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 g/lty7a16 tx+(uspv 4- cwi5jcmif p; 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 1.4v4/pb2b yc 8ar. What is the half-angle of the conical shock wave cb/4yp2vrb 8aformed?

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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 the1x- i-mlk-n 4da yjj79uae tf8 United States to Europe with a Mach number of 1.05 where the air temperd4x9m1ljkf iae-7u 8- ay-t jnature is $5.0 \; ^{\circ}C$. What is the speed of the plane?

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