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习题练习:Physics Unit12: Sound



 作者: admin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 falqg1;vni8 5 neqsk .yw:s2fnt/se 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 fastest thrasfhz -w7u48yk/bb j -ough

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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 avout dd(h e3b)hj9b7urm;( (j 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 happrhw a s(n:+p3wens to the velocity of sound? (Assume that all other factors remain const pn3+a:sr (hwwant.)

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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 s8d .t3g2zxfd oound, the velocity of a 200 Hz sound through air dg2.tdx ofz83 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 sound, the wavelelumy p)981f c1bvg;sength of a 200 Hz sound in a8)g9bpvmc1 y fs1l;eu 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 frequencie)o+ loi,nqe (7 sxlv2ws 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 thzu4yjg*: il 8gf5) izran 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*x;ewm3 lr-t awrej-8 in all directions. If you move to a point twice as far away from the source,*;3e8tlr -wme-ajr xw 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 m2bndxiq bhwp: 83,3s 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 s- *e4xx(kc sbt;k)chb ource at a distance d from the source is I. What is the intensity at a distance 2d xk(s tkh;cc b* 4exb-)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 frop 7en ws/xdi;i:+fzu.m a sound source that is radiating equally in all directions. What haxwe zip7/ :n .fu+;sdippens 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 sofl , 5bk-y(ry ;s5eksu x,fn9ource that is radiating equally in all directions. What happens to the intensity level of the sound? It drops b,-ukko x59( 5s lybynffsr;, ey

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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 sooco*qnrr u499qt(09*l5rt,udomk+qtw fu;a und 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 emitt1htj6uh-,4f m9tx (7 wzbydbht a2co(ing a pure tone. What characteristic of theh4wt -hcht y mj1txob62bd 7u9(, azf( 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" of a musical /rpik w8 qao;yks t y/;yg,kw.9abd50note?

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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 notx hxe +4vrn)b.e?

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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 w sm,-pc q(be0 ufd e(z5dmh1-dater

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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 t49hi; / r7c5dsrlyhaves 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 qvkzb n k5 .-5 bzhb*k)c kap2y 3/d3sfg5uf,aand the sound wave generated by the guitar as a result of this vibration. Wha kk.5a3b/zu )n5fvzhd2 b3p-s qy5 kacf*,kgbt 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 0yq8m :/ff d4isjcx ghs5;dj 1ends, 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 the wavelengthsf;.kijjp q g(3 of the three lowestjgjqi( k;p. 3f tones 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 one6- ialb0 47-9h6 wkjmobh*q0hgk(opap ax: qf of the following fre-m7 j 6p hxolakg(qbhwhq69akp b04 if-0:o*aquencies 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 leng 0vxec.y(p 5*trjp0x t)lrie- .sq:zlth L is resonating at its fundamental frequency. Which statement irc.t-x0szle* q) :.le0prtjp 5yxv(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 onedsv7 z)g 1qp9zbxdn*+ 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 the wavelengths of,/-0s kc 3rsw:zxav fluf*h3i lb2n;z the three lowest tones produced by this pi-hz lxw32vz;s,3f lus*cb kai0/ :frnpe?

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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 Hz. Which ofkw;p0wubxj,kr/l0k2 p 8t n g+ the following frequencies will pu,p j+t0wkgn x;80b/2krlwknot 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 frequen:7l +emhfdbr/ cy. W 7+eb:h l/dmfrhich 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 speakerbc c 2ag-n fjk29i7qp+s driven by the same source. Each speaker produces a tone with a frequency of 200 Hz on a day when ti7bj9pf-2 q2ag +ckcn he 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 waves should hayjy/t 3adf,3 fk.skc4 l7n31jvih kj9ve

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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 pawa(pq.j m3wx5rticular beat frequency is heard. What happens to the beat frequwp 5a (.x3qwjmency 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 ex0ua,80 zlky2q5zj 6va wsf in-plains

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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 hear6asa7(b(s k o/8xy c0jlv w;sid by the obser0scbsyaloxai;(vs 7k / (jw68 ver 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 observer. The frequency heard by thel9hv) ehw2lt:s w6e qo 1.d/gp obseqet/hw) pdho6.el2l: 9 1vwsgrver 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 d 7)7t;udwn,jh xx8ztdvo h;x 4ouble its MACH-speed, its half-angle will decrease by a hun4xdt8wht vj;7o;d ,x) xz7factor 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 ai3i(tuz 70ie cwr is 352 m/s. What is the air tempera0i 3izte (u7wcture?

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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 a+*(8 /laxlf .beml lvof 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 sounda7qdl0mo: 2p:lid kk cti11 j/ in air is 340 m/s, a bat emits a shriek whose echo reaches it 0.0250 s later. m1jpaq l/7di 02: i lkt:dock1 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. The temperature i rq1k+2e v- pnavy19w7-q jp9zocdc)es $0 \; ^{\circ}C$. 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 ofu.yv iu lbb;(4 lightning, the distance to the lightning sl(vi. 4ubyu;b trike 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 tempnv9u:+zk:ujj fu.*y v erature 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 and hear the s-,ltt y::z tryplash 2.5 s later. How deep is the well? (Ignore air resistance, and assume theytt:-ty ,r zl: 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 zsm60lvu o ve51y )1vwsound wave of 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 0q7oww* emo4z 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 o2. kdhe.5 ay :.xz,6zbptz pchf 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 a 70-dB p+dk v6xq7c,7sxf lf/5me0ndm7,my osound?

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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.s( fwpki;y imh s/;p, intensity levels of 70 dB and i ;hi f/.wsp(;pm ,syk40 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 ga mhh5rdr:w14atkk- x( hoa:g.rage is 100 dB. What is the intensity level generated by one d x(mwh5r14r.khaag-o :t h:kengine?

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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 +t9-a bgx1tzbin all direction+tbat-bz gx19 s 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 that is r2 92ox ewqhuc+1b/sqkadiating equally in all directions isubk c+ q/91esow2hx q2
$6.0 \times 10^{-10} \; W/m^{2}$. 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 be uniformly di3z3sfdq8jmk9 a w3-s; ioo3 mlstributed in all directions. What is the intensity level at a dkf d iosojl; s3mm-3z839wa q3istance 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 ifjz,0qe gm8 7cs 65 dB at a distance 5.00 m from a barking dog. What would be 0 7mj8 ,qfzcgethe 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 60 dB. What4bh ;g56fhyoqx 6 7e.a/mv5 sos7glkjz+gjx, is th/vl q4ejj ,ogxhgs;y56ago fz+ 65bxm. 7sh7ke 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 levev./-8bxfq qizts(ev 9l 5.0 m from a point source is 95 dB. At what distance will it b s/.9iq e8-zqxvf( tvbe 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 Hzx 9sj8(r *atxy. What is the frequency of the fourth harmonic?ty9xrja *8 (sx

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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 op ykbm;8fjzj4k0ax x/- en pipe is 900 Hz. What is the length of the pkb-j8kfxj0 4 xza/m;yipe?

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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 pipgq -mr)a qq;5(mgm8nd e of length L is 400 Hz. What is the frequency of the lowest qn;aq5mmqdg(rm) g8- 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 bolki(8y hy /u9(t 4aifyth ends has a length of 0.80 m. If the velocity of sound in air is 340 m/s, what is tf(h/u a 4tyliik(8y 9yhe 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.pu. -hplx3b8)-pq ux7 xuzimerature 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 jtm,q2 mt,w:.1jb pd qclosed at one end is 330 Hz. What is the frequencdjwmm,bp : .qqt ,t12jy 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 oxff4;0v, n(reli( ojfne end that will have a fundamental frequency of 60 Hz on a day when the vel(fj0ex;fl nfo 4iv,(r ocity 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 temperature isbcq.mlz -*n5pugh*. v/ kxau7jh 41a x $20 \; ^{\circ}C$. 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 o33bv z k3.t lhgjhze7zg-k.(xx4w5c 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 pla+jfwbk 7y:d (yyed when the speed of sound in air is 340 m/sw(fy+jykd b:7 . 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 tm 0ygcg05o)n4 h m x0vlt)s,ethe other is closed on one end. If the fundamental frequency of cy tlgg) x,ts0ve)040monmh 5the 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 j7f9k0njt/ )bj jn qx-frequency of 800 Hz in air where the velocity of sound is 340 m/s. How much farther back would source 1 have to b9nj7qjn )kj /bx tfj-0e 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 placilr) zq212 rrged side by side 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 frr2r)1rzil g2qom 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 440 Hz and 444 Hz. What is thepx-qc28+ s-lezsu j)c 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 tuni0b..7hpd u h0a fk+7sdgb uu:ing fork to tune the frequency of a musical instrument. Iff: du.spu.bhg7+0hi akd7u 0b the tuner hears a beat 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 and 7 m respectixu tb.o id,z/:vely. What beat frequency is heard when the horns at:o,uid.xb/ zre 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 are found to pr cvh1ft6)lakr7 9 u(xroduce a beat frequency of 2 Hz when a frequency of 660 Hz is played. Wh vr7cl k6h(1axu)9rtfat 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 stationard)3u vwqo,1ply 1000-Hz sound source at twice the speed of sound. The observerldv3puq ,ow)1 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 frequenc/3wd q:mswn) . qqgoh6y of 1000 Hz) approaches a stationary observer at one-half the spshnqd/g3 .q mwwqo:6) eed 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. 3mul1l cl+mdsep,7o9def0:a If a listener moves with a speed of 30 m/s away from the source, what ielul91 c+pofdad 0e 3 s,m7:lms 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 800-Hz siren. It is traveling at 35 m/s o ei7 og))21fc8x 3s yz-onbpnzn a day 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 observer hear?c8oni eo-sb 1g 3zpnyf))xz27

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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 whe3h : v;oxww 6m)k0z virn,dn;in a train approaches with a speed of 30 m/s. The frequency of the train horn is 600 Hz and the n x m:n;ik,6)3v id0hzvwro; wspeed 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 as7302obol js)m u c4x400-Hz whistlemo c0b sxluo4)3a2 js7. Take 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 towardbbbhis( ;2,p(y fc)fz a stationary train. The train blows its 400-Hz whistle. Take 2s;bzhc)f f,ibp( b(ythe 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 train blows it 8bfi1q1 xw+ c+f.owijs 400-Hz whistl+1 +ojx8 fiwqc w.1ibfe. 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 1c/d ) hlp/ 0zdtbu/k,z20 km/h. It blows its whistle, and you hear a tone of 400 Hz)c0h /b/zzk tld/ pud,. 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 speed of sound in air ixc, m2(dmr 6xys 340 m/s. What is the frequency heardycx(m,r6x d2m 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. Assume the speed of *lb 37jhgt) ax8 )vtyw8k2(vjsd2mqksound in air is 340 m/s. What is the frequency heard by an observer if the observer iqys8kx23 2 8kvt* blt(a)vjwjm7dhg)s 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 detec noh)lxtpne; j3 +-b1rmine the speed of an object. A 40-kHz signal is sent out, and a 42-kHz signal is returned. Assume th)p bj+x h-1e tn3no;lce 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 ssvop19dgv0 . an71k bwave 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-angl/c* . :a5rwk3eq kxihee of the conical shock wave :rkh.eaqk* / x iwc3e5formed?

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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 m.) fe5vwc;qfc rp6 9qthe United States to Europe with a Mach number of 1.05 cfpqefm6v ) 9r.5cwq; where the air temperature is $5.0 \; ^{\circ}C$. What is the speed of the plane?

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