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: 匿名未登录  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 a fals:3h tq/ rpbqv/e 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 fastest tuwf+35 jd- )i6vrjns c +xas9through

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 in a steely lj s6 do0i ga4e+i y4n;xcs+y6gg+ x8+mxl(t 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 tfq;7m 3a*b* sfk lp4mp*uh xe.he air increases, what happens to the velocity of sound? *.um*3x4pheps*bf l; f7 akqm(Assume that all other 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 a 400 Hz sound, the velocity of a 200 Hz soundhpaf5jtt)2 7x n0m/zs through air ifj 5h0npx7zt 2mt/s)a s

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 wavelengthh 3i5/wiilw( b of a 400 Hz sound, the wavelength of a 200 Hz sound in air /ih3 iwlbiw(5 is

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 frequencies greater than 20,000 Hzv+ 9*,mwfptbb4p kw0 z 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 wit o*zogjmo n s0oyvn1m,mix97-w7d-h+h frequency less than 20 Hz are called

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 al1b -m ohfuwkm na*f3j h3.w8+jl directions. If you move to a point twice as far away from the source,fhjmw3a+3 h-oufw.m*1 8kbn j the frequency 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 divergingsxism jw *d:8, waves, intensity 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 distbhjs*m+3 **mbd8zx s tance d from the source is I. What is the intensity at a distance 2d sjxhm bz3b8 s+*m* t*dfrom 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 that is radiating equally inuhxlnyzot4u5megt:ew 1 b9); ( v c8w5 all directions. What happens to the intensity of the soundx:8w5 vgtoceen )5uzl91tbmw 4 hy;u (? 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 radinpc 9wk97m6csd 5 x)ouating equally in all directions. What happens to the intensity level of the sound? It6sm)5nxc pck 9o d7u9w 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 bonbsci8 c 9b 7c+wr;/e5nzt;hecomes louder?

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. What charactercwl1wq3c11qktq7 glz nl/ a9)5mbmc;istic of the czq;nl )/tbcq 1q l1mckw35179gm lawsound increases?

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 "loudness" of a musicafrz 3a( )mum+sl 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 "pitch" p : brjv1lk*r :,-aofot x4hl: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 a*nd fxyz )3a9fbyl 75bir into water

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 waves ar /x5 j2 - 0zf)cxt;/fkabzeamre

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 the sound wave generated by twy179jbhk p9q-e foc5* q o*hthe guitar as a result of this vibration. What do these two p5eqo7h yf99* kb-jhcq1w o*t 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 wiur: lfain5wh r- +9p 9-dffm9hich is open at both 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 jry )j;y;tvo8 are the wavelengths of the three lowest tones produced by this p;o)y jryt8jv;ipe?

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 lthr7y zv2zmdoka5/cg2j . 0jt- ;4mupipe of length L is 200 Hz. Which one of the following frequencies will no hdzm ;jo7 4-yukmvj50/tc.ztgar22 lt resonate 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 fun pf3+5cvy1qo;i4 pnrp damental frequency. Which statement is coqcp1+r35iypo fvn 4;prrect?

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 iswxd +-ot 4tkp. open at one end and closed at the 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 pipeuq*hk 0(97 lossrof8h of length L. What are the wavelengths of the three lowest tones produced s 0so8f 9hlh*ko7(qru 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 lenq0c 0v;.v aipwgth L is 200 Hz. Which of the following frequencies will not resonate in that pipe0wv.0qvp ica;?

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 closed att)6r 4 e39as vdpspavu -3d4nji0du oc2y; vp* one end is resonating at its fundamental frequency. Whddcvatp; 2)yi 3-up0pj v o* sud4e3s46an vr9ich 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. Ea 8 vcjjin;+z.zch speaker produces a tone with a fr;jzn .zjvi+ 8cequency 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 so6)q .tp -ed,oprf 5x7d ,c dkao;cgzf8und waves should have

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 frequency is heard. +e xg/nuywb-b -oy5b6 What happens to the beat frgbe --5/6oxnyb+y wub equency 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 explainsot;:6zw r. klp

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 bzn: 1c0nlk4j a stationary observer. The frequency heard by the observer is:bjcnk 1nlz 04

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 from a stationary observer. -6nsmu;um i j5The frequency heard by the observ imsn jum5-u6;er is

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, i tfw-sl42 5xocgz /b4ets half-angle will decrease by a factor of: xez5 t/-c 2lfw4osbg4

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 ultrasonic 2+)*3,uilhmy ;t :qriivsmqlsound of frequency 45 kHz in air is 352 m/s. What is the air tei3 qutsm2;v lhy,lqm) *ir+i :mperature?

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 at:w/a)9b wjrp;q 0y4 7jzi ,n7zqnvhbd $0 \; ^{\circ}C$ 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, 5 q(0ze2zk 6si qk3amca bat emits a shriek whose echo reach26iqe amcz k5z(kqs0 3es it 0.0250 s later. 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 hear9 )efi te(e* (zimp7xw 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 ia.65 qurhvh+ ,ecas9, the distance to the lightning strike is abouhc r,a6ih5ua+. 9 evqst

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 thp ))cyk ;hsz) *dmea5kqsu0; ze temperature 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 deep well and hear cf9afq) yjc o l-+ix*0r f1k+qe8 dd1uthe splash 2.5 s later. How deep is the well? (Ignore air resistance, and assume the velocity of sound is 340 m/c-1 9+ ykofi1e8fja*d)cl q dr 0+xufqs.)

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 of a sound wave of frequency 50 w4)x/cqnmo4k0 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 ai;2ra 1io sl: qicmkq qc)*a:e8ihrb)4r 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.

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 level ofga qw4y11; b7fpx*5el ivm+rxjn7l8i 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 of a 70-dB slyu:1 6kc pw4d0tl x5zl,s2y iound?

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 witfy2wfa pf j46 scmnc 4k)w/k.-h intensity levels of 70 dk.)6 fjw-cy2/4smw nf4afpc kB and 40 dB?

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 is 100 dB. What is the inteh+w lg (04myf3z. etvpnsity level generated 4t .lv +fegpwz0y( hm3by one 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 distance of 6.0 m from a source that is radiating equall2 zpx 2m 7y)p;y:mkfwcy in zfk yw2mp:7 pcm ;)xy2all directions 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 diwsn5fpvec 2-*m8i nou;0)u awstance of 6.0 m from a source that is radiating equally in a 8e5wm -in w;cpv)uao*fs0nu 2ll directions 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 about 1 mW of power, whrkq.6nqhd nz5 (wiv 1-ich is assumed to be uniformly distributed in all directions. What ii-z5vwn.rk 1q(qh 6dns the intensity level at a distance 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. Whauk p/ana-* 6ywi3h/lht would be the intensity level if two identical dogs very close to eac6ia-3ahwh/ *uy/ plknh 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 sound source the intensity level is 60 dBoc +g 0at:h6pd. What is the intensity level (in dB) at a point 2.0 m from the source? Assume that the source rap dgh+o0a6 ct:diates 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 mgdh.7 qxxq a+.jd g w/p2xbtc p2wbq5w.*zt // from a point source is 95 dB. At what distance will it be 5h/ b2..a.qbptqww+wxxpzx* jc/gq7 2 d dtg/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 oct)1hdm e3n2pjrc/ej 3nr-: r uwk(lrxbp 4 3*f 1200 Hz. What is the frequek /1r lmxnr3j(ur) je-:whcbnc3 e *pprt3 42dncy of the fourth 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 hxvwn5s; m6hb 2t5qztw 8-.y 7mb(ekwsarmonic of an open pipe is 900 Hz. What is the length of the pipe?.s;k5q6w tvw -2nzy75 b (8btesmx hwm

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 iqk,mi grzf,w1/ 1:x bxhpab.k1 z7i u)n an open pipe of length L is 400 Hz. What is the frequency of the lowest tone that will reub1 1haz1 , .g k7impk,wxr/ifq:)bxzsonate 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 a length of 0.80 m. If the velocity 8itp-n.-gm3nag;/hhi,s1ah k (n9pzqyw )m mof sound in ainsp (g;gq.8hi3/ 1y)n,- a mtmz-ha wkm npi9hr 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 in9rclmsvqh 2( rc3 -kx, a room 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 ink.hngl kpqr 4*t*; 47l8tambt a pipe closed at one end is 330 Hz. What is the frequency of tt kt*gl*qtp4amr h874ln kb.; he third 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 .h3urcg7 brk5shortest pipe closed on one end that will have a fundamental frequency of 60 Hz on a day 3cg 5hru br.k7when the 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 temprz l19bm1w .p oaqb3w ;dq8l.rerature 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 )wtv+yfzwj sr(/5 of8 in 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?

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 0.75 m is played when the spq*,k6adll pwje0 nx 6+eed of sound in air is 340 m/s. What is the a e wkll,j+q6 x0dn*6pfundamental frequency?

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 uxo-x9mlphjbj;;n:9 l t/ 3azthe same length: one is open and the other is closed on one end. If the fundamenta9tm ol/x xbjjpu:;hz3nal- ;9l frequency of the open pipe is 300 Hz, what is the fundamental frequency of the closed 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 emit a frequency of 800 H3mf n.h igdh4.z in air where the velocity of sound is 340 m/s. How much fari dg.3mhh. 4nfther back 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 tf (/yf.ehaq2w)whi: 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 detectfay/eq ) f2hw: ht(w.is 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 and 444 +7fl0wu xxlk9 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 f1-aknt1 ztp3 aork to tune the frequency of a musical instrument. If the tuner hears a beat frequency of 2 Hz, what iaka1 ttp nz-31s 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 the sound(c8kkv7wqjz3 s produced by two horns are 6 m and 7 m respectively. What beat frequencyjk3 c(z7 k8qvw is heard when the horns are sounded on a day when the velocity of sound 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 two violins in a z7ucf5:w y0vc*g wfgb1,f c-in 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 tvf - ycw cz,w5f0g*cugb:1i7fhe strings would bring them to the same 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 twicniyh1t/j0nxza fij8z k 3 )5e1e the speed of sound. Thyazz 3jfej /0)ini85x 1h1ktne observer hears 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 (normait3aft( - .3cohka r;pl frequency of 1000 Hz) approaches a stationary observer at one-half the oh3kctp ;a ra(3-t.ifspeed of sound. The observer 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 a speed uhd3,k; 8ta4ibmugui o34a .d of 30 m/s away from the source, what is the frequency heard by the observeu8dk,mta.3odh4u 3agiu4 i; br? (The sound speed is 340 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/ap1;enh 0e brv+at-x+9d ar5rs on a day when the speed of sound through air is 340 m/s. have+10tr-; n9r rd +abap5ex The car approaches and passes an observer who is standing 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 hea6b39)blpt y sh (.lamerd by a stationary observer when a train approaches with a speed of 3(ybsb tpm6h )e3.ll9a0 m/s. The frequency of the train horn is 600 Hz and 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 toward you at 120 km/h. j7mw4:yfzp98 a.amtmtjx 5;hers;o8 The train blows its 400-Hz whistle. Take the speed of sound to be 340 m 58orjj7xat4 .;se m8mw zt yp;ha:9mf/s. What frequency 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 120 km/h toward a stationary train. The train wy dsy0(l2;w0dng8 5hknkv e)blows its 400-Hz whistle. Take the speed of sound to bs( gy k0hdv5wlnk;n28w )0edy e 340 m/s. What frequency 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 from7b 8h6 qdvmp-r.+b l* dbwyx8y you at 120 km/h. The train blows its 400-Hz whistle. p7.vbdr*+xlmb8 y6h w d8- byq Take the 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 atx-821 igvwed8eke :vq 120 km/h. 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 frequency of the whistxe v 182we8d:gk eqvi-le?

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 ey xh8kc 3v2(m4cj4qk Hz. Assume the speed of sound in air is 340 m/s. What is the frequency hmxch(448 ejc3 vkq2k yeard 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 )o *f n4db5tuz eumnj.8g.5d5xs/kj gis 500 Hz. Assume the speed of sound in air is 340 m/s. What is the frequeu)z 5g nbk. nd.5dt*/mj5ox84sueg fjncy heard by an observer if the observer is approaching the train with a speed of 30.0 m/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-kHz signal is w+ vpqmm9 ,a (mxjcp:;(wxt8asent out, and a 42-kHz signal 8q(( w mc;aaj:pm x9tvx wm+p,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 produced by a sus9pyx(fxh znlr,+8/x personic 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 of Mach 1.4. What is the half-angle of the conical shockmewkc+perbu6*8 - 4ik wave formed?mu + rcb8k *wkie64-ep

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 flies from the United States to E j3n 2 sdxlb(k3yz5-wnurope with a Mach number of 1.05 where the air tempern3n(5w2-3 zldsy kjxbature 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
    本系统支持习题练习,作业与考试三大模式,作业考试自动评分,成绩排序一键导出,可设定动态变量同一试卷千人千题
    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|使用帮助|手机版|切到手机版|题库网 (https://tiku.one)

    GMT+8, 2024-11-21 23:23 , Processed in 0.458974 second(s), 195 queries , Redis On.