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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 false stat ab7-6 wksrp8.2o rc4*tkatxa33 qd jpement?

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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 throu0kpd2v0fw.xu ;es os 1e4 vp0z5-eve fgh

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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 w/y05f qp ;thsa 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 happens to the velocity of soundsqrgc*/gwyov 41(gk 4? (Assume that all other factors remgrosqg/41 k*wgv c4 y(ain 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, theyc9;jvq coh.umwq22 kf1 ia,ry)1x -e velocity of a 200 Hz sound through a 2m .y2ey- f1,q1 cqw)vri a;juoxk9chir 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 wavelength of a 200 Hz sounqt7ye0q.e4 wt xycq 6; w18mvrd inc0146y;em t w8 7qr.qqxtey wv air 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 greatery cg2w9 pq/(ah 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 lesny2g nkbo : 1rq17woe1s 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 diky(*8j -x26wxoy d,uoxz9jt qrections. If you move to a point twice as far away from the source, the freque-dx9*6y o 8ozjq 2u wtjxx(ky,ncy 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 dive .lvd;z nsjv8q )a+f s8ba.zk6 *vxv(krging waves, 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 sourc6 ;nm+f qe+ t( vahvsbj2pc5p(e at a distance d from the source is I. What is the intensity at a distance 2d fro+tvvb 2a(+ (6 jp;escpn 5mhfqm 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 radu3da)h l;s.ntiating equally in all directions. What hap.nus)lhd; ta3pens 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 froma8 *f18ul wsyb a sound source that is radiating equally in all directions. What happens to the intensity level of the swb8*u 1ayf8lsound? 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 a( ,-jf;p rxy1nvf5zwxs a 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. What charf jy,ua bn8p3*acteristic of the sound ijbnafy*8,up 3 ncreases?

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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 notad8j l4 rlkgi re.4gc6j79 nf3e?

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17#
 
单选题 ( 1.0 分) 切至整卷模式 搜藏此题  
  What determines the "pitcghg*fm lnt a2; h:q0v, q;ly:vh" 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 jwm(mtc wa2do**: 2si 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 waveb 3cqfs/r( cho+97oc ss 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 twdd2 *sodr: -zhe sound wave generated by the guitar as a result of this vibration. What do these two waves have in common? d-*w dzsr2:od

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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,(9 - qib+wfp4swx ihb/ 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 areif sr;1nm3xb 3/8himk the wavelengths of the three lowest tones produced by this pipe3 /8s1 rb ;3khfimxinm?

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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 ie8vx1n gfq d:i+osq2:n an open pipe of length L is 200 Hz. Which one of the following frequenc8 qsqoe1+2 gi::v fxndies 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 frequency. Which st2i2s n:0lwh:g5lmdg5ivfe 3 catement 5lg:i e l50hgf: w2dsncvmi32is 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 on4rwd6y9c y r*ze 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 wavelengthrxz ( j9 15oh-gwmgbo;s of the three lowest tones proom9xz(wrb 5g g; h-1ojduced 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 resonat l.r:w uiz8n4zz-e6rce in a closed pipe of length L is 200 Hz. Which of the following frequencies will not resonateen4rz ciz ur8:-.6lzw 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 -jls +mxo+uw 20v62i+(ep2 ltvipwk xits fundamental frequency. Which statement is corre vtlew v-0k u 2(ilwp2xp sxmj6o+i++2ct?

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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 ufw880(7wo9 l qa yolpspeaker produces a tone with a frequency of 200 Hz on a day when the spee o0(a llpf9wu8oy7q8wd 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, ojapiu*n6ft11 ) izi 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 particular beat frequency is heard. fk hs(g)rr0)p What happens to the beat frequency if the frequency of one of the tones is ik gprh )r)0sf(ncreased?

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32#
 
单选题 ( 1.0 分) 切至整卷模式 搜藏此题  
  The Doppler shift explainn5bkw;cxcmfr*j4u) 2 s

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33#
 
单选题 ( 1.0 分) 切至整卷模式 搜藏此题  
  A sound source approgh ,d9xcv02 wfaches a stationary observer. The frequency heard by the observ 2f,9dw hvxc0ger 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 frequenua8 ah8nv bp- 537 ua5h2yk.fv(zykwfcy heard by the observer is 35hy8kwkbf2 y(u7a-zfp8naa vvhu5.

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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 will decrease by 4ynp,vy 5r4q5fo(r y nv(rgw3a fa 5(n y,4nvry5yq(or34v wr gfpctor 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 frequencyedrnfh xgct s00- l- 53wp(1by 45 kHz in air is 352 m/s. What is the apn0 0t31elh -(gsb- fycx5wrdir 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 air8u(h -j gs3adh 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 emi,djr w0e+ gkm4ts a shriek whose echo reaches it 0.0250 s later. How fg me,wjk+4r0dar 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 t p9nhtz-sh- +fe3tn8in 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 seeing a flash of lightning)zs9-p gahre 8, the distance to the lightninggr-a8 z 9eh)sp strike 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 k2l5twd3.o +n x ulrd6n,oyw: cliff on 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 ap i n3x 86+wob ewfbztj73 q.*5dqpw7and hear the splash 2.5 s later. How deep is the well? (Ignore air resistancae .ww n6+tbo53j bx7d8 pwzifp3q *7qe, 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 frequc3i1ejtr4 i- -mu-ua9buu4 pxpq:rk/ency 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 aiopjgdk)b 49 n,r 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 sound with inv38-b grx2ouytensity $10^{-3} \; W/m^{2}$?

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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 v gvyd32p 553zkdqvf/ a 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 intyp4d; ly6c z1yku3)hlnz-k/qe+ u :rzensities of two sounds with intensity levels of 70 dB and 6+-lk yy/ pun1r :u)k;zz y he3zldq4c40 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 kklq 2w6 ;js+cby 15 engines in a garage is 100 dB. What is the intensity level generated by one engine?js cl ;kq2k+w6

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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 i 1/qb s4)mhuorr+ /ffthat is radiating equally in sq4mr1hrf /)+uiobf /all directions 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 tdy*q zg;waf :cf*6ykzq 9o/*rhat is radiating equally in all dio*ay6 q9f/wz k*:; d frqyg*czrections 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 isu (knr)vxad4 1e(r10w*6o skn . orlqj assumed to be uniformly distributed in a n*o.6ualkk0or)dq1rn1j(rw e xs4v (ll directions. What is the 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 from a b,ic2gth(o/fcw1/hdj*akd 8f6k e ir1 arking dog. What would be the in/f1 /o18 kcdrhh(t 2ckgj6 ,awed* fiitensity 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 p6sc.ik *e6dxo +3ksi 60 dB. What is thk p6o.*k6sie3xidsc + 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 source is 95 dB. At whio :/e smd+3daat distance dsea3 md:i +o/will 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 complex tone has a frequency of 120h7s z+pou+ym,2 tyw/qh 6+ri o0 Hz. What is the frequency of the fourth h myhq6 isr+/ hp2zto, y+uow+7armonic?

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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 th(oj8mkf8jjxj+s c dcd4 5 a;+oird harmonic of an open pipe is 900 Hz. What is the lengtho+4 dc(jjod k;8x js5f+j8 mac 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 opym1:xy rxh an1zh,a.h*,v046 t hdpcuen pipe of length L is 400 Hz. What is the f.6a1 1 dxxzc:p4yt0nhm y,v ,ah*hhrurequency of the 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 ends has a length of apzz:.t9gm3 jjw3*he 0.80 m. If the velocity of sound in air za3z*e3: jmgtw.9jhpis 340 m/s, what is the 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 td06fy1.kxiya 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 frequency in a pipe closed at one*. 0ow8 qgjjpf-b vn9vik r3cjh5(*hn end is 330 Hz. What is the frequencjkn*0hf.pqcnbw( v58hj - j3r*9o igvy 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 one end that williea 8(m*-m)hnqfbi, i have a fundamental frequency of 60 Hz on a day when the velocity of sound ise)b anm,h(q* -f 8iimi 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 veszq i9 5s+z/8m2y ss1o6assis $20 \; ^{\circ}C$. 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 the xjxckwo3;k z016 + csltemperature 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 playedln a:*b hcc1uzak620o when the speed of sound in air is 340 m/s. Wh:ocau 1a*6 h zn0lbk2cat 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 lqn7:g8t :yl6se 7cx lxength: one is open and the other is closed on one end. If the fundamental freq: 7t7c n6lxxlgq:ye8suency of the 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 8fe/(er gxkl 8-00 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(g8 l-kfee/x r 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 pla8a k9psaf3mjgj i-:/zced 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 from the person to the other speaker? (The sound speed is 340 m/mk/js:j zgf-ap9 8ia3s.)

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69#
 
单选题 ( 1.0 分) 切至整卷模式 搜藏此题  
  Two tunes have frequenci 3sj2vc2t :yu,/qvwrnes 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 t49r*2 qxvfs pzadge; 3uning fork to tune the frequency of a musical instrument. If the tuner hears a beat f2d 3* gevrzfp9x; 4sqarequency 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 twov p jacie16rx7:o (w r2gy/8u 5 df(tjv6qmh3x horns are 6 m and 7 m respectively. What beat frequency is heard when the horns are sounded on a day when the velocity of sound i3m pa(v2 (jj7f6x toi r vqwr:5euhgx1/86cdy s 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 st dsb6nk4yt 19wrings on two violins in an orchestra are found to produce a beat frequency of 2 Hz when a freq41 t wsby9dk6nuency 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 s,f9g; qlim 58iprc,lztationary 1000-Hz sound source at twice the speed of sound. The obs;9 izi,gr5 pcl8q f,lmerver 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 e:w 32;;3disbn+qi2ut9ph fehj awc3 Hz) approaches a stationary observer at one-half the speed of sound. The observer hears a frequency o9pi+ 3jeiq :e t2b323sn hwdwu;;hfacf

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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 1000hoiryb ex18 62e-7ysm Hz. If a listener moves with a speed of 30 m/s away from the source, what is the frequency heard by the observer? (The sound speed is 340 1yoeme2 8hy7xr-ib 6 sm/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 day whe99h0v4 tep3gi gnijo:n 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 frequenc0:i evoth3n4g9 ipg j9y 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 statipvz9*67b prb z.xx:y4k:r d5vsvd:hd onary observer when a train approaches with a speed of 30 m/s. The frequency of the train horn is 600 Hz and the speed of sound is 340 m/s.:zyv59.7 x ddvzrp*hsrxvb 64b:k :d p

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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 12m. f:1i3n lenna67ymm 0 km/h. The train blows its 400-Hz whistle. Take the speey6a3fm 7ml:eninn 1m.d 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 toward a stationary train. The train blows it-x0 bi.zor ;fe7; 5bzhjv,hnas 400-Hz whistle. Take the speed of sound to be 340 m/s. Wi - ;hxn5j;v,hzeo0abr. 7zbfhat 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 40 m4g-ip:kj(bhfzdqkn/ ,5.fr0-Hz whistle. /(fqf4jh:m b zk k,dgnr5.p-i 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.;1 n2iwzgnm; sjz6 qe. It blows its whistle, and you hear a tone of 400 Hz. Take the speed of sound to be 340 m/s. What is the actual freq.6zq;j wni ge2;n1mszuency 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 v+ ol:fn dxw9xaj+53eoy.m*,a; szw yis 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 moving away from the train with a speed of 30. zs;,da+yo.oxnvm wweaj:9*+x ylf5 3 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 sbc 5dn0i+r*x,j fz5vj ho1- e*y4j;w* svmupupeed of sound in air is 340 m/s. What is the frequency heard by an dvb,fx; +4 o*1p*5 jyz-w s*cumr h0i5ujev jnobserver 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 determid b -n(h)a. y7drnq.zs3z ix,zbh0v+gne the speed of an object. A 40-kHz signal is sent out, and a 42-kHz signal is returned. Assume the speed of sound is 345 mhd3 sh7.ax0qb- n n, iv(yb)zz+grzd./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 j1ucg2i84swaai y 7y9 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 z3 dauufx5 j q:xsi:/kw28e,mconical shock f5iszx ju:q /,:xeka 3m8uw2dwave 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 flie:d g2s+vb bh-fs from the United States to Europe with a Mach number of 1.vbf:g- 2s d+hb05 where the air temperature is $5.0 \; ^{\circ}C$. What is the speed of the plane?

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