51fly国际课程 (51fly.win)

 找回密码
 立即注册

手机扫一扫，访问本页面

 

      

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
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

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 false statementi: q2a oar37ml?

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 7 st ge4a2vu86ot5vxj fastest 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 in a steeqtpp+g:f5q r)6 hm47ah l2n5 vnt va:cl rod?

参考答案:    
本习题练习全部题目来源于51fly国际课程 (https://51fly.win)，学生可自助刷题练习，扫右侧二维码加微信，获取学习资料，答疑辅导
教师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
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 cwp */re 7v2nless+ v9of sound? (As2 pe+*vlw7 / 9snscervsume 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 souf +op(c)l:pq4 vso .ptnd through air ist):sppv+f. (ql4o o pc

参考答案:    
本习题练习全部题目来源于51fly国际课程 (https://51fly.win)，学生可自助刷题练习，扫右侧二维码加微信，获取学习资料，答疑辅导
教师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
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, th7 a:ywrd g)6 o/-gzbvve wavelength of a 200 Hz sound in air is vvwog r/g7-bd )z:y6a

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 t nvi1h1vm :)unhan 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 thg8c3:kfi(6 dri60hnrdvwn :mw4z, fq an 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 6gkj m1lbwg5 z *l3ug)all directions. If you move to a point twice as far away from the source, the frequency of the sound wi*bgwmuzljggk 65l3 1)ll be

参考答案:    
本习题练习全部题目来源于51fly国际课程 (https://51fly.win)，学生可自助刷题练习，扫右侧二维码加微信，获取学习资料，答疑辅导
教师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
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, intensity is prop0k)w mio 5qokc(9 p-lxortional 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 distance d from the source is 8ek* ci4 a(k7fvg3jwuoh2de1I. What is the intensity at a distance 2d frdu ok 783(cafg1kee2 *jwi hv4om 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 fr 0 g;6ycd bvtc0** fm347 xx*fcxmuzewom a sound source that is radiating equally in all directions. 7cg6;3fyct4*vx x e*mwm*zc00bu fxd What happens to the intensity of the sound? It reduces to

参考答案:    
本习题练习全部题目来源于51fly国际课程 (https://51fly.win)，学生可自助刷题练习，扫右侧二维码加微信，获取学习资料，答疑辅导
教师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
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 sou4vmy( e,saqi0 rce that is radiating equally in all directions. What happens to the intensity level oymi,0 sqav4e (f 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 followingnqq br:q ya6r 8ze((x; increases as a sound becomes 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 characte)fb bi380kqkql9 9iuna0-ffpristic of the sound iib0pa9)k qqfil9 u3ff- n 0kb8ncreases?

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 "loudhgkk;auo:vjoao83,2lz q7( i ness" 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 "pitch" of a musical note?n zbe .: ffva9p:2 rzj.g5b,kp

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 wat.ykxjfp :9c*:u i m8kper

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 displace/vauo6r-/ mh gment waves 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 guitarxpo(nkar) 4r0 xg*)x0 rfm+vq string and the sound wave generated by the guitar as a result of this vibration. What do these pa+ )q)r0xrmnfo 4 xgk*r0x(v 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 whiy 2gy5d oq5de/-wju f5ch 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 lendt7 wtr zlr0bht2 7fpyqn596d1 r(qa(gth L. What are the wavelengths of the three lowest tones produceb9rh(d5 627 7rlf0qnrd1ttzt( a w pyqd 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 length L n5 d k+2hbgft1g-hmu5/i 4zfpis 200 Hz. Which one of the following frequencies will not resonate 2gf u4+zpthf n/51dgmib h5-k 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 isu(:ma 8l 3iei4p6g pxts fundamental frequency. Which statementa36i(g8ulp4s e:m ix p 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 the own:7y /bqpi6e1 ldy;p ther, 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 of the three lowess;.hosib2 q+xhc 5a ad92 jn/wt tones produced b5ns a.d i 2/qh+hbxoj;as9w2cy this pipe?

参考答案:    
本习题练习全部题目来源于51fly国际课程 (https://51fly.win)，学生可自助刷题练习，扫右侧二维码加微信，获取学习资料，答疑辅导
教师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
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 /a. (hqyewqt/ in a closed pipe of length L is 200 Hz. Which of the fywq(e/. hat q/ollowing frequencies will 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 closed at one end is resonating atc;3(wb ltktq+.s fl p) its fundamental frequency. Which statement is .wpt( sllkb;3cq+) f tcorrect?

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 s/ ;wbimd6z g7lfx i+r 0p/lc7ppeaker produces a tone with a frequency of 200 Hz on a da d +ir l/7wp07;fxibgzp6 m/cly 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 m 0cbn78btii0zoevpa *y(zo yu7q31 lz 6z+9ibeats, the two sound 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 hear0sr9kut04swbam7zk +d. What happens to the beat frequency if the faubk 09z7 mwk0s t4r+srequency of one of the tones is increased?

参考答案:    
本习题练习全部题目来源于51fly国际课程 (https://51fly.win)，学生可自助刷题练习，扫右侧二维码加微信，获取学习资料，答疑辅导
教师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
标记此题
32#
 
单选题 ( 1.0 分) 切至整卷模式 搜藏此题  
  The Doppler shift explains dju*ywkkp5( 3mj 8u2s

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 stationary observer. The frequency heard by the obl:f/d)it3mr kc.o k+v serve+/rdf) kkvl oc3i. :tmr 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 from a stationary observer. The frk1xpr;c- r yr)bbf)i p 8u9plrt(;e:9vtni9kequency heard by the obs(b1ipxntb9 -er 9r;pyrivf t l)r:9)cukp k8;erver 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, its half-wtram4 cs ).v-angle will decrease by a facw.c )rsv -t4mator of:

参考答案:    
本习题练习全部题目来源于51fly国际课程 (https://51fly.win)，学生可自助刷题练习，扫右侧二维码加微信，获取学习资料，答疑辅导
教师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
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 sound of frequency 45 kHz in air is 352 8c ,d4p *xlvkp 22zwbam/s. What is the air tpc*2wd8ab, x24lk pvzemperature?

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 ofg1csb3z*omlj ;,)qz m8 avoz- sound in air at $0 \; ^{\circ}C$ to the speed at $100 \; ^{\circ}C$?

参考答案:    
本习题练习全部题目来源于51fly国际课程 (https://51fly.win)，学生可自助刷题练习，扫右侧二维码加微信，获取学习资料，答疑辅导
教师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
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 emitqc,kr k 7f)2sw b;j:kvs a shriek whose echo reaches it 0.0250 s later. How farrbkj,q2 cw k7) vsfk:; 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 hear the echo c: wau .(s /rqn .nnxt(urhv7l 9fg2p2in 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 e,trt6dqvxnu y/l9, -lightning, the distance to the lightntre,6yu x qn-,v9/ldt ing strike is about

参考答案:    
本习题练习全部题目来源于51fly国际课程 (https://51fly.win)，学生可自助刷题练习，扫右侧二维码加微信，获取学习资料，答疑辅导
教师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
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 frspz) g7rd3s0q7bphs-c : dimde9z.c6om a cliff on a day the 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 d 53nz*:6 ;kvcmhue zcreep well and hear the splash 2.5 s later. How deep is the well?n h*eukzr: mvc5;c 3z6 (Ignore air resistance, and assume the 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 of a sound wave of fkxmrbx z q7va8i0 9l:9requency 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 airv(7ac96av xcgsv 5x lbf sg(o 14eg/b0 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:    
本习题练习全部题目来源于51fly国际课程 (https://51fly.win)，学生可自助刷题练习，扫右侧二维码加微信，获取学习资料，答疑辅导
教师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
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 of a sounw6 6okjbd(dx 7y/)qua d 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 sound?1 zuu;yv2lcisi,.cy7

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 yfs : 6die f0u7r ,f8+:+hdpj6nw smwaof two sounds with intensity levels of 70 dB and 40 dB?u8: wwspn 6m+ejddf,rha 6fi0+ f7 y:s

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 enginek1 rkpl jxs4js7qm/2* s in a garage is 100 dB. What is the intensity level generate/jpqsx*j12 kr s4 lk7md by one engine?

参考答案:    
本习题练习全部题目来源于51fly国际课程 (https://51fly.win)，学生可自助刷题练习，扫右侧二维码加微信，获取学习资料，答疑辅导
教师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
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 distanc(gr(eu)pz gl/t )sm/be of 6.0 m from a source that is radiating equally in all direcmpu/r/b((l z)s)gg e ttions is
$6.0 \times 10^{-10} \; W/m^{2}$. What is the power emitted by the source?

参考答案:    
本习题练习全部题目来源于51fly国际课程 (https://51fly.win)，学生可自助刷题练习，扫右侧二维码加微信，获取学习资料，答疑辅导
教师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
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 distance of 6.0 m from a sour4ib4zn6aru .r)rq n2 ace that is radiating equally in all dire2ir4n)q na6 r4uab r.zctions 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, which is assumed to be unier8a 93bg z-vzformly distributed in all directions. What is the z-brv39e 8a gzintensity 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 dt;ep j(cc:x;gx fy 97xog. What would be the intensity level if two identical dogs very close to each other are barking xcfx;jt(x;c7g: 9yep ?

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 dk.:d7q1ddlamw ta u5( B. What is the intensity level (in dB) at a point d qd(wl.:1tadaku m572.0 m from the source? 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 source is 95 dB. At what dist:p7. *pghpxdru gq 77fance will it be 7g :pg rd*7hf u.7xqpp75 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 1200 Hz. What is thedvqv)/6 k1o .apmm8dy frequency of the fouva1d8 ).qm my/kv6 opdrth 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 harmonic of an open pvtif .;erkf xr w-axa 3q,1m0 h.ld,p;ipe is 900 Hz. What is the length of the piperqpka3a- ,;fx.h r1.e xd ;mvf,iwl t0?

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 o;ap; wc0xw yzm0, r0abf length L is 400 Hz. What is the frequency of the lowest tbzwx;m;wy0a0r pc0 a ,one 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 a length of 0.80 m. If the vel );w+mte- n nx(3uvlewocity of sound in air is 340 m/s, what is the frequency of the second harmoni3(umw+)l;v nntx-e ewc?

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 agpikh.pljh: *i40p .a 2jb7og 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 in a pipe clos nz3scmrg.: 6bkf. ,cnj+g q6xed at one end is 330 Hz. What is the frequency of the third harmonic?.nqgr +gf:kj63c ,.cmbx6n sz

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 closec xhny)wq5 ,l4 k8wsqkxa6/9dd on one end that will have a fundamental frequency of 60 H,/ kxkw6x 8n qc4hlsqya9w5)dz on a day when 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 t: aslipp 7l2dtx0nu9+ p qp;3pemperature 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 where the temperatu/d.jyg t6+ 89t ccy7ccoxhvz3re 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 w,iekpasr ex (7r*s4 t:hen the speed of sound in air is 340 m/s. What is the fundamental frequency:esrr s,tixa7ekp*(4 ?

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 the sameb.k tk9.sbg 6-lq3 oxz length: one is open and the other is closed on one end. If the fundamental freq3obkl9sb. qt zx. -g6kuency of the open pipe is 300 Hz, what is the fundamental frequency of the closed pipe?

参考答案:    
本习题练习全部题目来源于51fly国际课程 (https://51fly.win)，学生可自助刷题练习，扫右侧二维码加微信，获取学习资料，答疑辅导
教师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
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 emiu3 rpabh o16e,t a frequency of 800 Hz in air where the velocity of sound is 340 m/s. How much farther back would source 1 have to be moved so an1a,r63ohepb u 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 a/ke ,j k0f dijl+rqruja/lk.7 6:;k knnd 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 r/76:jf;ukk. kadj/ni0 lkk,qel r + jm/s.)

参考答案:    
本习题练习全部题目来源于51fly国际课程 (https://51fly.win)，学生可自助刷题练习，扫右侧二维码加微信，获取学习资料，答疑辅导
教师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
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 .d lni0vd)o2y444 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 t5;go o,pos ,h550-Hz tuning fork to tune the frequency of a musical instrument. ,gs ot;opoh, 5If the tuner hears a beat frequency of 2 Hz, what 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 the sounds produced w4xmiudk4-rs. q(th7pu7oj .s0k0ow by two horns are 6 m and 7 m respectively. What beat frequency is heard when the horns are somo( kxo kw.7-hpwusj4urt 0q.d4s0 7iunded 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 twon xyy*200far y violins in an orchestra are found to produce a beat frequency of 2 Hz when a frequenn0ry0 fyxa2y* cy of 660 Hz is played. What percentage change in the tension of one of the 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 sqj 8 bud6r3hl:yn (uz v;7*bs1000-Hz sound source at twice the speed of sound. The observer 3s*sju6 u 7vb8r n; lyd:zbhq(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 (normal frequency of 1000 Hz) approaches a kf t1+-pd0rxzstationary observer at one-half the speed ofptr d+1z 0fxk- 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 ,im4nt5l 9 ifea listener moves with a speed of 30 m/s away from the source, what is the frequency heard by the observer? (The sound speed iemtf9ln,i5 4 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 sic64w3h g yeu:xren. It is traveling at 35 m/s on a day when the speed of sound through air is 340 m/s. The car g:4 h3 y6wxecuapproaches 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 heard by a stationaf1q+rc: m57flck r:ex ry observer when a train approaches with a spefrq+lc : r51c 7x:efkmed of 30 m/s. The frequency of the train horn is 600 Hz and the speed of sound is 340 m/s.

参考答案:    
本习题练习全部题目来源于51fly国际课程 (https://51fly.win)，学生可自助刷题练习，扫右侧二维码加微信，获取学习资料，答疑辅导
教师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
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. The train blows its 400-Hz whe ;w-50nezcy;wy pd,j istle. Take the speed of sound to be 340 m/s. What frequency do you 0 we,5zcy jewp-;ny;dhear?

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 stati7qm05bta h8nby +nd )lonary train. The train blows its 400-Hz whistle.b nb5)ht7dy + am8qn0l Take the speed of sound to be 340 m/s. What frequency do you hear?

参考答案:    
本习题练习全部题目来源于51fly国际课程 (https://51fly.win)，学生可自助刷题练习，扫右侧二维码加微信，获取学习资料，答疑辅导
教师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
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 train blows its 400n vq n,5(lby-v-Hz whistle. Take the speed of sound tlvv(nn y 5-bq,o 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 f/e3,h5 pu/:lmsaxs/f j 8qzysrom you at 120 km/h. It blows its whistle, and you hear a tone of 4ujs h z/,a/ey /pfxms: sq53l800 Hz. Take the speed of sound to be 340 m/s. What is the 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 i ,kuuf0+dj nllw *6n-es 500 Hz. Assume the speed of sound in air is 340 m/s. What is the frequencyfke l *l, 0nnjwdu+6-u 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 r -tpz)3 .sv mwxi r(2kdn6/sphorn 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/rmp (2 n .vrz w3si6ptkd-xs) 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 determinovad:pb;6dsqs0 sc d3wl55 -ne 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 m/s. How fast is the object moving?cdqd; 6sls:d5vp-onbs0 w35a

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 sap:g+,k v(tatp o3j hm6d;i; produced by a supersonic aircraft is $60^{\circ}$. What is the Mach number of the aircraft?

参考答案:    
本习题练习全部题目来源于51fly国际课程 (https://51fly.win)，学生可自助刷题练习，扫右侧二维码加微信，获取学习资料，答疑辅导
教师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
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 grx,3 c7o4vs s1.4. What is the half-angle of the conical shock wave formed?grxssov ,7 c43

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 S g bws42pau*r/tates to Europe with a Mach number of 1.05 wherg 4b/rw asup2*e the air temperature 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

    试卷内容到此结束!   © 2024 51fly国际课程 (https://51fly.win)版权所有

    浏览记录|使用帮助|手机版|51fly国际课程 (https://51fly.win)

    GMT+8, 2025-5-8 08:11 , Processed in 0.512426 second(s), 216 queries , Redis On.