题库网 (tiku.one)

 找回密码
 立即注册

 

      

上传图片附件

未使用图片

小贴士: 允许的图片文件格式为: gif, jpg, jpeg, png, webp,上传完成后会在上方生成预览,用鼠标连续双击缩略图,或拖动缩略图,该图片就被绑定至本题,显示在题目下方

本次作答已使用

小贴士: 此栏目显示的是当前作答使用的所有图片,绑定到某一题目的图片同时会显示在该题目下方; 删除使用的图片会将其转移到<未使用图片>类别


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: 游客未登录  开始时间: 22年08月07日 09:59  切换到: 整卷模式

标记此题
1#
 
单选题 ( 1.0 分) 切至整卷模式 搜藏此题  
  Which of the following is wp- u9m6rqk8f a false statement?

参考答案:    

标记此题
2#
 
单选题 ( 1.0 分) 切至整卷模式 搜藏此题  
  In general, sound is conducted b)fr, *t3xbf7xm gk s5fastest through

参考答案:    

标记此题
3#
 
单选题 ( 1.0 分) 切至整卷模式 搜藏此题  
  What is the speed of sound ic:zkp /c,nm6v0jm 8oan a steel rod?

参考答案:    

标记此题
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 oe2w*zulj+.7lne gw u8ij.jod4mhbb 0 (f2 z:g f sound? (Assume that all otherzw g8j0 u .gbb4(.z+lnfmdjh:u7io*je 2 2wel factors remain constant.)

参考答案:    

标记此题
5#
 
单选题 ( 1.0 分) 切至整卷模式 搜藏此题  
  Compared to the velocity of akqm66tgw e.i: 400 Hz sound, the velocity of a 200 Hz sound through air6qekgw: . im6t is

参考答案:    

标记此题
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 sound/)s;*czpxf vv6fzj1 a in air iv s;p*ja6fzx/vc 1z )fs

参考答案:    

标记此题
7#
 
单选题 ( 1.0 分) 切至整卷模式 搜藏此题  
  Sound vibrations with frequen 7aaijio;bd7ga*cox)m7 k r;x,4afq 7.nmj7rcies greater than 20,000 Hz are called

参考答案:    

标记此题
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 calle c)cg ,tawq,8f9d,ky r(o5 y1fvz nbg9d

参考答案:    

标记此题
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. If h(/fwfrt0+c 0dkb4yac0 jqf7 you move to a point twice as far away from the source, the freque4 (w0 rkffthfdb7j c 0aq0cy+/ncy of the sound will be

参考答案:    

标记此题
10#
 
单选题 ( 1.0 分) 切至整卷模式 搜藏此题  
  For spherically diverging waves, in5 .h/kalr) xj xnid26ztensity is proportional to

参考答案:    

标记此题
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 distanmcpn6g6+esimwd1( ;/ -e s 6cszpwpv.ce d from the source is I. What is the intensity at a distance 2d from 6wpespz 6+1/cv;es.wgmscd6(i p mn-the source?

参考答案:    

标记此题
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 tha1/+p)o bfjxl7; ue cwtt is radiating equally in all directions. What happens to the intensity ;ue+p/b7jl1tcwo )f x of the sound? It reduces to

参考答案:    

标记此题
13#
 
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 radiating equally in5w9l0m3q l;8) l poez:msxvhg all directions. What happens to the inte8pl03m;voqlm) l e9zwx: g5sh nsity level of the sound? It drops by

参考答案:    

标记此题
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 lok rizo2 * /.gt 86/0kdp-e zsmaew:kdxuder?

参考答案:    

标记此题
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. Wh: 7fs /cndsn8vat characteristic of the sound increas/ncfn87:s dvses?

参考答案:    

标记此题
16#
 
单选题 ( 1.0 分) 切至整卷模式 搜藏此题  
  What determines "loudnessu;pr gkn qk,+t(g3hh9" of a musical note?

参考答案:    

标记此题
17#
 
单选题 ( 1.0 分) 切至整卷模式 搜藏此题  
  What determines the s 3vyu:1 :y5)u v wtba;i9pbdo"pitch" of a musical note?

参考答案:    

标记此题
18#
 
单选题 ( 1.0 分) 切至整卷模式 搜藏此题  
  When sound passes from air into wate 0dkidf6, rsf0r

参考答案:    

标记此题
19#
 
单选题 ( 1.0 分) 切至整卷模式 搜藏此题  
  Pressure and displacement waveimam:y2g .c4 is are

参考答案:    

标记此题
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 tipjg7sh: 7 pp9he sound wave generated by the guitar as a :7s gip hjp9p7result of this vibration. What do these two waves have in common?

参考答案:    

标记此题
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 bmm7g/cy wo 07nq fb89xoth ends, there

参考答案:    

标记此题
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 wavelengths of the threeg gsi cxj24-n6x/ o-dv lowest tones produdg-x/x g4ncos-6iv j 2ced by this pipe?

参考答案:    

标记此题
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 len:*-ko6nctw u*l k jmcl rm4p11gth L is 200 Hz. Which one of the following frequencies will not p l m ml11oc**:4kutnwjk6-crresonate in the same pipe?

参考答案:    

标记此题
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. m3t9 -jphgmvw3hz, ce1gj .0z Which statj h zt33c pmjem.,0 1gh-z9gvwement is correct?

参考答案:    

标记此题
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 closed at 5s4uv.sr .q pithe other, there

参考答案:    

标记此题
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 oo bj3u+mgx + xr/dbgejig0 ;13f the three lowest tones produced3/j1e;udojm0 bibr +x+gg 3gx by this pipe?

参考答案:    

标记此题
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. W4up (w km;8dta)( yflbhich of the following frequencies willd8m lbt 4p wy((kauf); not resonate in that pipe?

参考答案:    

标记此题
28#
 
单选题 ( 1.0 分) 切至整卷模式 搜藏此题  
  A pipe of length L clo( uqfqes5i0f4p8 frk/sed at one end is resonating at its fundamental frequency. Whicfq0u4f /i 5k(rfqsp e8h statement is correct?

参考答案:    

标记此题
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 spucw/q zk1u-y 4 u 4 udbgko+a7d7y+5bs 6kxc.oeaker produo +6u a5x1boy4yc. /wukzu dcdk- +ksg7 4qb7uces a tone with a frequency of 200 Hz 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?

参考答案:    

标记此题
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 kml yhgb1yrdyee 9i5m 73v itu:*6b( 0have

参考答案:    

标记此题
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 freque f*9 r7x d(kw.am1xblcncy is heard. What happens to the beat fre cxar9 b* kdf7m1(x.wlquency if the frequency of one of the tones is increased?

参考答案:    

标记此题
32#
 
单选题 ( 1.0 分) 切至整卷模式 搜藏此题  
  The Doppler shift ex irq r+enfp ;bl466w amwp/5/pplains

参考答案:    

标记此题
33#
 
单选题 ( 1.0 分) 切至整卷模式 搜藏此题  
  A sound source approaches a stationaryon*/d w5k ycs8 observer. The frequency heard by the observn dysw*85ko/c er is

参考答案:    

标记此题
34#
 
单选题 ( 1.0 分) 切至整卷模式 搜藏此题  
  A sound source departs fro 5 h;jmf-pr lrtrg,6(vg 8uh:em a stationary observer. The frequency heard by the observer ;mjv rr8, r6l5(:hfghetp g-uis

参考答案:    

标记此题
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, ja9ih4vr k:8m cx+h6m::j irmzzdq/3 its half-angle will decrease by a fzk :jmh 9h8 qzri /rvmj4:a: d+mi6cx3actor of:

参考答案:    

标记此题
36#
 
单选题 ( 1.0 分) 切至整卷模式 搜藏此题  
  The speed of an ultrasoni.buqds),4 p. e n d6iwukhv0q.c sound of frequency 45 kHz in air is 352 m/s. What is t e bniq0.4)q.uds6u dkwhp,v.he air temperature?

参考答案:    

标记此题
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 awbhia2 kn w(h )w -q5d2cu3)v6fn0rj0jf7rn l t $0 \; ^{\circ}C$ to the speed at $100 \; ^{\circ}C$?

参考答案:    

标记此题
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 w5kwjt 2co hb- vy.5i2myuzyf)d,28li0/opd uhose echo reaches it 0.0250 s la/o5b.5khi-2p )d,v 20ylocfutd2 yzyi8 jw umter. How far away was the object that reflected back the sound?

参考答案:    

标记此题
39#
 
单选题 ( 1.0 分) 切至整卷模式 搜藏此题  
  You shout at a cliff, and cy *vjbi+0.w/lpab(j hear the echo in 4.00 s. The temperature is $0 \; ^{\circ}C$. How far away is the cliff?

参考答案:    

标记此题
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, the distance toc: h-njcl,7gp the lightning strike is abo:g-7lhnc c, pjut

参考答案:    

标记此题
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 tempera*2p1k ,mfdb71 mndrfj ture is $15 \; ^{\circ}C$. Approximately how far is the cliff from the observer?

参考答案:    

标记此题
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?

参考答案:    

标记此题
43#
 
单选题 ( 1.0 分) 切至整卷模式 搜藏此题  
  You drop a stone into a def sofs-t6qx +1ep well and hear the splash 2.5 s later. How deep is the well? (Ignore air resistance, and assume tff- qso1st6 +xhe velocity of sound is 340 m/s.)

参考答案:    

标记此题
44#
 
单选题 ( 1.0 分) 切至整卷模式 搜藏此题  
  The wavelength in air ofyo.x2 +y*gj)d.d ps ps a sound wave of frequency 500 Hz is

参考答案:    

标记此题
45#
 
单选题 ( 1.0 分) 切至整卷模式 搜藏此题  
  Sound traveling in air at 7/9tc*)rh8 2 l gzc::slbk4yshkv eki $23 \; ^{\circ}C$ 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.

参考答案:    

标记此题
46#
 
单选题 ( 1.0 分) 切至整卷模式 搜藏此题  
  What is the intensity lma0 n; 4exz)dhevel of a sound with intensity $10^{-3} \; W/m^{2}$?

参考答案:    

标记此题
47#
 
单选题 ( 1.0 分) 切至整卷模式 搜藏此题  
  What is the intensity 1o l(kzh+jk o8 ;8,yyfyq.n;il7usxn of a 70-dB sound?

参考答案:    

标记此题
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 intensity len3lv;pp.pe+ vwf 41oaww,c. k vels of 70 dB and 40 d1 +w veknf.pp4w3;awpo. vcl, B?

参考答案:    

标记此题
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 i; ny.o 2-f6dm;sxtkv-+ ziydss 100 dB. What is the intensity level generated by one .d v-if;;2+tks y myz6ox-nsd engine?

参考答案:    

标记此题
50#
 
单选题 ( 1.0 分) 切至整卷模式 搜藏此题  
  The intensity at a dis+d2ctudie8/)ghlsuya( i ;( btance of 6.0 m from a source that is radiating equally in all l/heb 2 (i(+u us;c)ddi8 gytadirections is
$6.0 \times 10^{-10} \; W/m^{2}$. What is the power emitted by the source?

参考答案:    

标记此题
51#
 
单选题 ( 1.0 分) 切至整卷模式 搜藏此题  
  The intensity at a di7 qawjxe(q h*/stance of 6.0 m from a source that is radiating equally in all dir /*qq(xj7 ehwaections is
$6.0 \times 10^{-10} \; W/m^{2}$. What is the intensity level in dB?

参考答案:    

标记此题
52#
 
单选题 ( 1.0 分) 切至整卷模式 搜藏此题  
  A barking dog delivers about34e c8g qz h3pv7h9ygh 1 mW of power, which is assumed to be uniformly distributed in all directions. What is the intensity level at a dis8e9h3y vz4hgp3chq7 gtance 5.00 m from the dog?

参考答案:    

标记此题
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 barking dog. Wo; c+ fy/f2ss ss5rbb)hat would be the intensity level if two identicab2r;ssf5y+c)s bf/ sol dogs very close to each other are barking?

参考答案:    

标记此题
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 s4*mjm1 e4jn ipound source the intensity level is 60 dB. What is the intensity level (in dB) at a point 2.0 m from the source? mj1e4mj*np4 i Assume that the source radiates equally in all directions.

参考答案:    

标记此题
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 sourceidvwzr. evgx,/ 47 x+q is 95 dB. At what distance wille4 wr/xzg7q v,idxv+ . it be 75 dB?

参考答案:    

标记此题
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 6j;z i1j d.zs c*hxzv)1200 Hz. What is the frequency of the fzcd.*6z z )hjs1x;vijourth harmonic?

参考答案:    

标记此题
57#
 
单选题 ( 1.0 分) 切至整卷模式 搜藏此题  
  The frequency of the third harm5d ob+zd6n7ax8 wyb; dnc e/hia0 8+ltonic of an open pipe is 900 Hz. What is the length oan x6i5 bn zwt+c yedahd/l0 7b;d88+of the pipe?

参考答案:    

标记此题
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. Whatj. -uxrxrt6kr.u, 4h f is the frequu f.6 xxjkr 4hru-,tr.ency of the lowest tone that will resonate in an open pipe of length 2L?

参考答案:    

标记此题
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 av:qltldk ryl1a//u ar:oz18zzo (l0, length of 0.80 m. If the velocity of sound in ai0r tyko udl8: z/ l1rq/ lv,oal1z(:zar is 340 m/s, what is the frequency of the second harmonic?

参考答案:    

标记此题
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 ryc m881e;,sz f l1rg4zbjnv7room where the temperature is $20 \; ^{\circ}C$. What is the fundamental
frequency if the pipe is open at both ends?

参考答案:    

标记此题
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 33mr( nd u,ql * q,umnti-b19z,g0 Hz. What is the frequency of the thirdrg 9 ,-(tqu, u* mdnmbn,ziq1l harmonic?

参考答案:    

标记此题
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 clos8d- zmn2van0ieh7 *xk rt,uf4ed on one end that will have a fundamental frequency of 60 Hz on a day when thtuakrx8e7i4 vzmnh-f2, nd0* e velocity of sound is 340 m/s?

参考答案:    

标记此题
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 temperaturoe:9 udre*eu75 kn4fxi58u-yf 5dqhle is $20 \; ^{\circ}C$. What is the fundamental frequency if the pipe is closed at one end?

参考答案:    

标记此题
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 wher mxj)5 ei68dzx;ml8lqe the temperature is $20 \; ^{\circ}C$. What is the frequency of the second harmonic if the pipe is closed at one end?

参考答案:    

标记此题
65#
 
单选题 ( 1.0 分) 切至整卷模式 搜藏此题  
  A closed organ pipe of length 02 (lgdqb8g:vd;4d 1 -: vx,udoi czvvv.75 m is played when the speed of sound in air is 340 m/s. What is the fundamental frvdv ::d 4,v 2g(vcoblu8vdzgq d1x ;-iequency?

参考答案:    

标记此题
66#
 
单选题 ( 1.0 分) 切至整卷模式 搜藏此题  
  Consider two pipes of -goq;r.ex w 9e6v3itpto5n/ uthe same 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/v e5 .;qox69oregpw-3tti nu pipe?

参考答案:    

标记此题
67#
 
单选题 ( 1.0 分) 切至整卷模式 搜藏此题  
  Two adjacent sources each exe 3e9n.k0tzxmit a frequency of 800 Hz in air where the velocity of sound is 340 m/s. How much farther bac09z3 exn ket.xk would source 1 have to be moved so an observer in front of the sources would hear no sound?

参考答案:    

标记此题
68#
 
单选题 ( 1.0 分) 切至整卷模式 搜藏此题  
  Two speakers are placed side by side 4xu p ;r :o6pwttis6 0jfk5gu8and driven by the same frequency of 500 Hz. If the distance from a person to pp8sg xkt665;:oi0 ujw4frtuone 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/s.)

参考答案:    

标记此题
69#
 
单选题 ( 1.0 分) 切至整卷模式 搜藏此题  
  Two tunes have frequencies of 440 Hz;a72.s)l7y jisl zny j and 444 Hz. What is the beat frequency?

参考答案:    

标记此题
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 c2)f9oy 0 24kq-bgnmr;po fr sthe frequency of a musical instrument. If the tuner hears a beat frequency of 2 Hz, what nb2q 2)f94oyrck0o;gsprm f- is the frequency of the instrument?

参考答案:    

标记此题
71#
 
单选题 ( 1.0 分) 切至整卷模式 搜藏此题  
  The wavelengths of ty d-th 6dj9x1vpeq 6rkzfm *2,he sounds produced by two 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 soydt,*zm9pfe 1 2kd 6vxjhrq6-und is 340 m/s?

参考答案:    

标记此题
72#
 
单选题 ( 1.0 分) 切至整卷模式 搜藏此题  
  The corresponding violin strings on g:f goz *y8am0n6lry-two violins in an orchestra are found to produce a beat frequency of 2 Hz when a frequency of 660 Hz is played. What percentage change in the tension of one of the strings would bring them to the sa6gn 0oy-ymalr*zg: f 8me frequency?

参考答案:    

标记此题
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 spee s7j- gbl,;duj ;1osl/zm*y jdd of sound. The observer heab*jd lljdz1s;7/ y,gjmu; -sors a frequency of

参考答案:    

标记此题
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// 7ljdpfbcq qtku0 mf;/7.mjr at one-half the speed of sound. The observ0mkmjf/q/uct/ .7bjp;dl 7fq er hears a frequency of

参考答案:    

标记此题
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 *i9 ;qg5hhcnwcadx u 2 s).3soa speed of 30 m/s away from the source, what is the frequency heard by the observer? (The sound speed is 3g;*.9 co sc3d s5i2 n)uhqhawx40 m/s.)

参考答案:    

标记此题
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 when the s1 if 5-4s8gqh4oxr,wf qna*hu.r 0canpeed of sound through air is 340 m/s. The car approaches and passes an observer who is stanr xs,f-r.g4f*aca 0hw8uq h4n iqo1n5 ding along the roadside. What change of frequency does the observer hear?

参考答案:    

标记此题
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 traiumn 6t)fb8et2eh2x 8+j ji )men approaches with a speed of 30 m/s. The frequency of the train horn is 600 Hz andtm)nhmbt26f 2xej)ji88ee u+ the speed of sound is 340 m/s.

参考答案:    

标记此题
78#
 
单选题 ( 1.0 分) 切至整卷模式 搜藏此题  
  A train is traveling im l x0ep /dpqcaa:5gy x9j5jdx1;w+g )3b ;fvtoward you at 120 km/h. The train blows its 400-Hz whistle. Take the speed of sound to be 340 m/s. What frequ0mfgx gp/ed95 c3b;a qi:;j vdj1ax+5px)ylw ency do you hear?

参考答案:    

标记此题
79#
 
单选题 ( 1.0 分) 切至整卷模式 搜藏此题  
  You are moving at 120bex6+ ++nqgw c km/h toward a stationary train. The train blows its 400-Hz whistle. Take the speed of sound to be 340 m/s. What frequencqbe wg+nx+c+ 6y do you hear?

参考答案:    

标记此题
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 tr3af 1 tcoovi42ain blows its 400-Hz whistle. Take thcitf 4va oo312e speed of sound to be 340 m/s. What frequency do you hear?

参考答案:    

标记此题
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 whqa-bjt4+ uk n)f,mko9 6 -wjlyistle, and you hear a tone of 400 Hz. Take the speed of sound to be 340 m/s. What is the u4jnk) -+tow 9j kb, yalfm6q-actual frequency of the whistle?

参考答案:    

标记此题
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 of4 , sj,th0qlhq sound in air is 340 m/s. What is the frequency,q0hq4j ,ltsh heard by an observer if the observer is moving away from the train with a speed of 30.0 m/s?

参考答案:    

标记此题
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 air)o dr178lqew*g 9zcx m 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 w*q)d 7r8eg cx1ol9zmm/s?

参考答案:    

标记此题
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-kHcxq1 hed94 9cmz signal is sent out, and a 42-kHz signa cm xeqdhc4991l is returned. Assume the speed of sound is 345 m/s. How fast is the object moving?

参考答案:    

标记此题
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 produq ;xbx*3o 2 btc,nv9jxced by a supersonic aircraft is $60^{\circ}$. What is the Mach number of the aircraft?

参考答案:    

标记此题
86#
 
单选题 ( 1.0 分) 切至整卷模式 搜藏此题  
  A jet flies at a speed sf a4j bt-uv9 7xh41/s4em baeof Mach 1.4. What is the half-angle of the conical shock whs4 7us4/mej1 avb49b exf-a tave formed?

参考答案:    

标记此题
87#
 
单选题 ( 1.0 分) 切至整卷模式 搜藏此题  
  The Concord airplane flie* *7lr ibun pwsrg9r(go8 ,md/s from the United States to Europe with a Mach number of 1.05 where the air temperatu9 n/r*wb(o , 8u* is7rmgplgdrre is $5.0 \; ^{\circ}C$. What is the speed of the plane?

参考答案:    

总分:87分 及格:52.2分 时间:不限时
未答题: 已答题:0 答错题:
当前第 题,此次习题练习共有 87 道题
本平台(https://tiku.one/)支持练习,作业与考试(自动评分)三种模式,群组成绩统计排序导出,题目动态变量实现同卷千人千题
如果您对本系统感兴趣,想加入我们或者想进行任何形式的合作,请加微信 skysky1258

浏览记录|手机版首页|使用帮助|题库网 (https://tiku.one)

GMT+8, 2025-10-29 02:08 , Processed in 0.450016 second(s), 195 queries , Redis On.