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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 pkf,nk.q/s pq5s;6ry4w /z e ma 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 conduge1 vsw)xbqgp69e; + cmw..gn;fhw *ected 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 ilj*;ud4,agdeld 2 yusk*j+ (sn 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,it/ x im a.,jmkr;-fp- what happens to the velocity of sound? (Asspij a., mik-/-mx trf;ume 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 veloccnnb+9 +t4f*y q2/ i*qsvhlqeity of a 400 Hz sound, the velocity of a 200 Hz sound through air iqn*fsb/+*9c vtqn eqly2hi4 +s

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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, the wavelength of a 200 Hz l-vb 9nr )2sfnnf2w))y+gyto sound in ant 9 wby-))f2+ nro2vn)flgsyir 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 greater than 20,000 yll0hxlfu:525. xj jhbx28jc 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 ar z3mza 58dr (9rbkzg vhwoge(;;3n.fle 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 dirc)oxl.rid wx +h/0wi3ections. If you move to a point twice as far away from the source, the frequency ww/ 0lr.i+h3x)cio d xof 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 wasd bn5/* wjpd)8lv5rrves, 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 dis t lj ,x3n3(m:g*lkqamtance d from the source is I. What is the intenjg,* 3anq3l m(xtkl:m sity 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 distance from a sound source tpn*basp c (u* ycwcw0g .68-mxcue./d hat is radiating equally in all directiowsu.pwx 6ny8- (u/0 cd*eb.cg* pcamcns. 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 from a soq9e5xc cu)ln k5vrq*x mn-s 80und source that is radiating equally in all directions. What happens 8k)e90qnr5n -vq* 5l xxcmcu sto 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 becomes loudem7u( (+eyg9d ;ohjlsj r?

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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 characteristic of t*u htu w e498q4od6jzfhe9 q*fj4hu d u64zweto8 sound 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" hhco t,k1r4di,)+swa n2z +h tof a musical 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" of a musical notehs 8hd/nffd,j0 h *;ri?

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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 intw,c 1kog3go 9p pdm,+to water

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19#
 
单选题 ( 1.0 分) 切至整卷模式 搜藏此题  
  Pressure and displacemen4e q0s-2;5k uroxsnent 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 o o0i(cdu wl1gb,evw -3n a guitar string and the sound wave generated by the guitar as a result cdwv, el i3 uowg-01b(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 o)xpylub ; s s2)8fb4yqszl:-qfl:fp+pen 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. What are thep)l7vqb**spq wavelengths of the three lowest tones p*v )bq splq7*produced 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 of length L is 200 Hz. Which va1ue + z;x0im/h*czbone of the following frequencies will not resonate in the same pipe?i; /+mu c1zb*ae 0hxzv

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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 fundam./sn*rro):x*dcij s jental frequency. Which statement is correndijj ro*x.s r*)/sc: ct?

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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 )ro6qe ffkb( f+p.* d0rg1e8bub tzz/ 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 the wavelen q29i 4wo+8bvis v-jejgths of the three lowestj ji 24s-wi +9vqe8bvo tones produced 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 epplp8;6 gp0ain a closed pipe of length L is 200 Hz. Which of the following frequencieapgp806p l;eps 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 ;qe vx;;m( jyz np:hk/is resonating at its fundamental frequency. Which statement is corremzhvq x(;/kpnej:y; ;ct?

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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 sp,kdd 8rb px7z1eaker produces a tone with a frequency of 200 Hz on a day when the speed of sound is 330 m/s. The person rkxp8z dd7b,1is
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 waves shouldg (5bgvramdvp,y4 * o8 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 frequi.*/mqrv, uuwt1cr 5nche o.;ency is heard. What happens qvroc/;t ,u1wm 5hi.uc.e *rnto the 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 explai-zi2 oo,:5 raa ckm5crns

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33#
 
单选题 ( 1.0 分) 切至整卷模式 搜藏此题  
  A sound source approachesq lx*77ng5wn5mk8u3drlc))a;b ue f v a stationary observer. The frequency heard by the observe)l7bv5d;wu xq*lrn7egca8 )mn k3 5fu r 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 stationary observe aww glq3/jf5v(/6efvr. The frequency heard by the observ w6v/j(afgw q/e 5lv3fer 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/oa 1,r5,n*jt alknsk , its half-angle will decrease by a factort, jla 5*or/ ,s1nankk 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 ofq20 n.n7rah cv 7mtau: frequency 45 kHz in air is 352 m/s. What is the air temperatacatqm 2u n0n :7rv.h7ure?

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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 vsg*s(nn +9u1ap 6vo(7 absew 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/s, a bat emits a shriek whojx7v -iukn+e q6. goex3l:h0n c(i:oh se echo reaches it 0.0250 s later .hc3u e iq:k(joi nxh-7gxl6n:+e0v o. 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 s. Th*eo ng2wxn+(c e 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 seeings/r0s*i s;yvdcz- 6p c a flash of lightning, the distance to the lightning stri*rp d/ z0 ysssc6icv-;ke 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 temperaturzl6viklbnc r 7 jes4+q-p)99ve 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 4mt*tg 2yu 2*s/ggbfdwell and hear the splash 2.5 s later. How deep is the well? (Itd2syf u/4bg*mg t2g*gnore 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 vz+)ranl; 66u, h70vq fekzedHz 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 -+/+(xuaa*zkdn qzwn$23 \; ^{\circ}C$ 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 intensip. ;4x26d z yyqqdwx:qty $10^{-3} \; W/m^{2}$?

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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 souq-7 lcx o3d4ab1ubuprd v0z4 6nd?

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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 twoecfm)y 08e c4tai)k, m sounds with intensity levels of 70 dB and 40 de8c k fcm ai)m4ey0t,)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. Wci.98xvyn tr 6;nj+an hat is the intensity level generatn8.+ntyivax;j c69r n ed 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 nx 6 0tuue dl*w6+ye/kthat is radiating equally in all directions iuw*kd0/e+6 enuytlx6 s
$6.0 \times 10^{-10} \; W/m^{2}$. 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 3s)+ x*md, sae;kfh jtthat is radiating equally in al,; a3 +dshtfxkj es)*ml 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 assqb -91z:cg5tj+xmhw rr lvc4- umed to be uniformly distributed in all directions. What is the inteb5xcm+jz: qlwr1-r9h c-g4t vnsity 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 fro. edff;o5 nsbz3k e4,om a barking dog. What would be the inteo5e;34 nbdskf fzeo,.nsity 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. Wrd9w*pqy)abdn(epmg m9- yl q.pcyv9.8 e, w0hat is the intensity level (in dB) at a point 2.0 m from the source? Assume that the source radinml. d gd9pe8w)w*p r9py-ecqb0,yv(9 m qa .yates 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 poin d+ril((. dbtzt source is 95 dB. At what distance will it be 7 (zi.dd+t( lbr5 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-,sv6xogo :s z a frequency of 1200 Hz. What is the frequeovs : z,sog-6xncy 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 b:tkqycr- +e -o8a.wn pipe is 900 Hz. What is the length of ttc-+k arq.n -:8w beyohe 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. What is 5v oix zlk:o g -l;ih+ egqk7x//2zyb9the frequency of the lowest tone that will rixx ye2gv /ql o ;+-il/5zbghkko9:z 7esonate 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 veloc(2d*6yy/zl)x:sbjr jfu0eb dity of sound in air is 340 m/s, what is the frequency of the second harmo:sbz /uf(jy2bx*r0ejyd6)d l nic?

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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 amu7bn/y-ula 9x smg62 room where the 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 frequen)htqa ,h g0,)52cup civ1x ioxcy in a pipe closed at one end is 330 Hz. What is the frequency of the chq 1gix,atx) u )0p2vi5cho ,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 5w)x02 bk 4lp(l+ xmyy+cet6rfmt *oishortest pipe closed on one end that will have a fundamental frequency of 60 Hz on a day when the velocity of sound isx iocx)2bywlfme64 *5tmy kp+r0 (+tl 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 temperatu 6-scte en8:pure 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 roo bw,03qt qa 78v4bf+g x;ao,6ilbvqrpm 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 when the speed of sounu 7n3300 udkxsscf)b jd in air is 340 m/s. What is thek3d0) js7uufn cs3 xb0 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 th /d.1a8i+rkamgv q .mbe other is closed on one end. If the fundamental frequency of the open pipe is 300 Hz, what is the fundamental frequency of the cloaiqg+av81m.k dm/b. r sed 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 lx*/ dzkcs14wa frequency of 800 Hz in air where the velocity of sound is *skc4lx wd/ z1340 m/s. How much farther back would source 1 have to be moved 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 side and driven by the sam,cds .cw(rj/knr /bdo*4 m i2ge 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 admwscd// k*.r (gj2,bnico 4r 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 44f tq;9odb8 uv4on8/bk0 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 frequency 8 3gyycko0skbof8o4tg x5iwr 3 94:ep of a musical instrument. If the tuner hears a beat fb9w3ps g y83ei4:t0 kfygoko4 xr 5o8crequency 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 byu* : fzzj, 7p7r:unnas e2.obe two horns are 6 m and 7 m respectively. What beat frequency is heard when the horns are ss:eb z.pz2,rfnu:e* ju7ano 7 ounded 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 strin dq i-qmc42zv)gs on two violins in an orchestra are found to produce a beat frequency of 2 Hz when a frequency of 660 Hz is played. What percentaqdvz4q-c i2 )mge 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-Hz sound source at twice the spekz dvzr6a/0h 6ed of sound. The observer hears a frequency o6zhz/r vkd6 a0f

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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 freqk*yqn94 ot kabz b2kz;f/1li4 uency of 1000 Hz) approaches a stationary observer at one-half the speed of soundk/f 9 1tqoi;bzykz*ak44 2n lb. 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 with a speed of2y 1eg9s)w9di:f er fn 30 m/s aww) fi 2fgy 91d:nsre9eay from the source, 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 80n 6zv.)iuah. p2kmj /j0-Hz siren. It is traveling at 35 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 zak/ hup. jm.2nvij)6standing 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 apprstu(xfg0: +w ro0oy0joaches with a speed of 30 m/s. Tg+f0 : 0j0txruwys oo(he 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 blow3eyzyylago 2o*0a)m3k y)9 jys its 400-Hz whistle. Take the speed of sound to be 340 m/s. What frequency do youyyaym)gzky* 3)0elo a29 o3 jy 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 e mj)q4s+ 1qjftrain. The train blows its 400-Hz whistle+s4q1 j) jqemf. Take the 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 thgrb()idt wb cw)/3jc -45bu mrain blows its 400-Hz whistle. Take the speed of t) h)bic/mrd- wj (wbb4 53ugcsound 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 *pny 00hrsf*b its whistle, and you hear a tone of 400 Hz. Take the speed0 srh y*pbf*0n 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 trainulwhuf5xanifkj6p/y/ ag 8j+ m d*:/: horn is 500 Hz. Assume the speed of sound in air is 340 m/s. What is the frequency heard by an observer if the observer is moywuuf: j/ h/ k6*m 58/paani:+ljdfxgving 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 sp 6 *rhvj6ydiyqive 47b sw3bk9-i:u(j eed of sound in air is 340 m/s. What is the frequency heard by an observer if the observer is approaching the train with a speed of 30.0 m/ vd(jyyih4i rbs*6 6jkiv 39wqe7b-u :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 signagasm1q.rtn t:.b *y l9l is sent out, and a 42-kHz signal is returned. Assume the speed of sound is 345 : myt1*gtb.qars9l n.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 aircrafto lji0ho l6a(k;+7 j6r+ mrdme g(zc,k 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. Whar,dpub aps1 5djn)fih6w-0 ,ht is the half-angle of the conical shock fd,apun)r ,h wd p1h-65b i0jswave 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 flij clbkz0 ej w..,7mqq/es from the United States to Europe with a Mach number of 1.05 where the air temperature isj e ,qclzj /.bw.km7q0 $5.0 \; ^{\circ}C$. What is the speed of the plane?

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