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 Unit18: Electric Currents
本习题练习试卷来源于51fly国际课程 (https://51fly.win)， 为试卷打印版，您也可以在网站平台(https://mail.51fly.win/)直接 访问本试卷的在线电子版并查看正确答案与解析，搜藏保存任意题目到收藏集。 访问方法: 平台首页左上角"通过试卷号快速访问"输入试卷号 76，并点击直达试卷；或浏览器地址栏内直接输入本试卷链接 https://mail.51fly.win/test76.html  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。
 作者: physics  发布日期: 2022-08-17 11:19    总分: 80分  得分: _____________

答题人: 游客未登录  开始时间: 22年08月17日 11:19  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  
  A device that produces electricity by transforming caj 4c)p5r:xbv1t 90i fyf uy1ghemical energy into electrical energy is called1xtgy)fa5 yjc b:9if4 0vpru 1 a

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  
  A car battery

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  
  The total amount of charge that passes through a wire's full cross section atw p)7 ,0spitob any point per uw) ,0sp bti7opnit of time is referred to as

参考答案:    
本习题练习题目来源于51fly国际课程 (https://51fly.win)，学生可刷题练习，扫右侧二维码或加微信xxxxxxxxxx，获取更多资料
教师可以抽题组卷或一键复制本试卷，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  
  The direction of conventija1n-2atw0+ a ky8fkpon current is taken to be the direction that

参考答案:    
本习题练习题目来源于51fly国际课程 (https://51fly.win)，学生可刷题练习，扫右侧二维码或加微信xxxxxxxxxx，获取更多资料
教师可以抽题组卷或一键复制本试卷，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
5#
 
单选题 ( 1.0 分) 切至整卷模式 搜藏此题  
  A coulomb per second is thft,q yf6l vtv; +12sile same as

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  
  Car batteries are rated in "amp-hou )xl7ttt qf9q1rs." This is a measure of their

参考答案:    
本习题练习题目来源于51fly国际课程 (https://51fly.win)，学生可刷题练习，扫右侧二维码或加微信xxxxxxxxxx，获取更多资料
教师可以抽题组卷或一键复制本试卷，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
7#
 
单选题 ( 1.0 分) 切至整卷模式 搜藏此题  
  The resistance of a wire isuyu4l* 9qf:t0ovh. bae3r *gg defined as

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  
  What is $1 \; \Omega$ equivalent to?

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  
  The resistance of a wirxc ;ud5f95e re8jj3blz:cy6 g e is

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  
  The resistivity of a wire depends o1 ge-qd7) 7la ocbpp:in

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  
  Which conducting material has the lowtfh v g1eq8;pgvh +5w ik3g(q 8yy)yb4est resistivity value?

参考答案:    
本习题练习题目来源于51fly国际课程 (https://51fly.win)，学生可刷题练习，扫右侧二维码或加微信xxxxxxxxxx，获取更多资料
教师可以抽题组卷或一键复制本试卷，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
12#
 
单选题 ( 1.0 分) 切至整卷模式 搜藏此题  
  Consider two copper wires. One has twice th ja/qtm1jo q a:002syre length of the other. How do the resist j 0sa:q20q/j mtao1yrivities of these two wires compare?

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  
  Consider two copper wires. One has twice the length of the othe)g8f+w;e0dy l2l6z .d tq vppcr. How do the resistances of thesez2glf .tcy6pd)e w v;q p+0dl8 two wires compare?

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  
  Consider two copper wires. One has twice the cross-sectiongm:u+a6a 3odx /+p8 yrh6 dcsfal area of the other. How do the resistances of these a86a+sud o/rg+3: hfdpx 6ycmtwo wires compare?

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  
  Consider two copper wires. One has twice theer q 12,abevu, length and twice the cross-sectional area of the other. How do the reqeb2,au, 1vre sistances of these two wires compare?

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  
  The length of a wire is doubledfdfy b-sf.j5; and the radius is doubled. By what factor does the resistafffsd .yjb5 ;-nce change?

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  
  How much more resistanctw s: ;hrpm 3,hk*rz) .j6wbpue does a 1.0 cm diameter rod have compared to a 2.0 cm diameter rod of the same length and made of the .pm; ,s) kb6hj* whw3:zptrrusame material?

参考答案:    
本习题练习题目来源于51fly国际课程 (https://51fly.win)，学生可刷题练习，扫右侧二维码或加微信xxxxxxxxxx，获取更多资料
教师可以抽题组卷或一键复制本试卷，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
18#
 
单选题 ( 1.0 分) 切至整卷模式 搜藏此题  
  The resistivity of most common meta nlr6aaiw 9mn 7wo p6h-t 4e9i/qak04dls

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  
  Negative temperature coefficw jf9;iw5cu 0mients of resistivity

参考答案:    
本习题练习题目来源于51fly国际课程 (https://51fly.win)，学生可刷题练习，扫右侧二维码或加微信xxxxxxxxxx，获取更多资料
教师可以抽题组卷或一键复制本试卷，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
20#
 
单选题 ( 1.0 分) 切至整卷模式 搜藏此题  
  What is 1 W equivalent5(no:8zp4j1 wr,d8qzc d7u 6gser ucu to?

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  
  A kilowatt-hour is equ8o8qwn w4/f50awf.h5pvj r clivalent to

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  
  If the resistance in a constant voltage circuit is doubled, the power dissipa3vg lb3 cu sn1v8v7ui:ted by thabc8g 1v7i:u lv3s3nuvt circuit will

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  
  If the voltage across a circuit of cu mrwa3*)ae 4uonstant resistance is doubled, the power dissiwuu4 raem3*a) pated by that circuit will

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  
  If the resistance in a circuit with constant current flowing is doubled, t,*v7 /7a0 o oya2eewsetej)pohe power dissipated by ,07e o /2yeop7 ve otasj*wae)that circuit will

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  
  If the current flowing through a circtiqd7zd 2t edr-,oa(3uit of constant resistance is doubled, the power3 qz2t,a to-7r( didde dissipated by that circuit will

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  
  During a power demand, the voltage output islba fgun+ 9avnz.98 0p reduced by 5.0%. By what percentage is the +apb9gzfu9 nn. 0lv 8apower on a resistor affected?

参考答案:    
本习题练习题目来源于51fly国际课程 (https://51fly.win)，学生可刷题练习，扫右侧二维码或加微信xxxxxxxxxx，获取更多资料
教师可以抽题组卷或一键复制本试卷，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  
  A current that is sinusoidal with respect to time is referred tokc7n:g p3wjt4g 6ymw9 as

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  
  Consider two copper wires l-hsb z,14lmx w4 p blc7(4kbieach carrying a current of 3.0 A. One wire has twice the diameter of the other. The ratio of the drift velocity in the smaller diameter wire to that in the larger diameter wire iwxihl- zblkc 4s47m 4,p1b(lbs

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  
  Materials in which the resistivity becomes essentially zero at very gpwh*yk8;f c (n ,qjhe i(egbuz6xjm// 5tl *5low temperatures are referredq kcfxj8p(i,m*eyu5zwj ;5ne */ /tg l6(bhhg to as

参考答案:    
本习题练习题目来源于51fly国际课程 (https://51fly.win)，学生可刷题练习，扫右侧二维码或加微信xxxxxxxxxx，获取更多资料
教师可以抽题组卷或一键复制本试卷，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
30#
 
单选题 ( 1.0 分) 切至整卷模式 搜藏此题  
  What current is flowing if 0.67 C of charl l4:opq+ odag4p o4;uge pass a point in 0.30 s?

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  
  A charge of 12 C passes through an electroplating apparatus in 2.0 min*xd7*z3kyd d c,:ila l. What is the avelk7dz y :l3xa*di*, cdrage current?

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  
  How much charge must paji mniob8.f0p.w du;1fhh.;css by a point in 10 s for the current to be 0.50 A?

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 total of $2.0 \times 10^{13} \; protons$ pass a given point in 15 s. What is the current?

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  
  What current is flowing if )1qhgwcuba95 $4.0 \times 10^{16} \; electrons$ pass a point in 0.50 s?

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 $3.0 \times 10^{15} \; electrons$ flow through a section of a wire of diameter 2.0 mm in 4.0 s, what is the current in the wire?

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  
  A coffee maker, which draws 13.5 A of current, has been left on f cj6ba;i* o:vuor 10 min. What is the net number of electrons that have passed through theciaob*v6 :j; u coffee maker?

参考答案:    
本习题练习题目来源于51fly国际课程 (https://51fly.win)，学生可刷题练习，扫右侧二维码或加微信xxxxxxxxxx，获取更多资料
教师可以抽题组卷或一键复制本试卷，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
37#
 
单选题 ( 1.0 分) 切至整卷模式 搜藏此题  
  In an electroplating process, it is desired to deposit 40 mg of silver oru dx: fdj*u9ok0); jfog 6a,kn a metal part by using a current of fd9)j d6kfoo0 kug;x:, rjua*2.0 A. How long must the current be allowed to run to deposit this much silver? (The silver ions are singly charged, and the atomic weight of silver is 108.)

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  
  What potential difference is required pe a2ltnsfe */c(06hf to cause 4.00 A to flow through a resistance of 33/f2h0 ltafe* sc p6e(n0 W?

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  
  What is the voltage ao3gr9a+l1 r;ca on5oe6fvqd 7 cross a 5.0-W resistor if the current through it is 5.0 A?

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  
  A 4000-W resistor is connected across 220 V. What currenta6*igp tz;z k7 will flow?

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  
  A light bulb operating at 110 V draws 1.406w;::5x a d iwunynwx* o,zen9 A of current. What is its resistance*dyonnzi;a 59u6wwwex:,x n: ?

参考答案:    
本习题练习题目来源于51fly国际课程 (https://51fly.win)，学生可刷题练习，扫右侧二维码或加微信xxxxxxxxxx，获取更多资料
教师可以抽题组卷或一键复制本试卷，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
42#
 
单选题 ( 1.0 分) 切至整卷模式 搜藏此题  
  A 12-V battery is connected to a 100-W res:d dhl z 7vhefoca(2nn*my18/ istor. How many electrons flow through the whn1y7l e/(ncadd8 :fh 2*zvmo ire in
1.0 min?

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  
  What is the resistance of 1.0 m copper wire of diameter 0-*dk3z /k6qqjwm, gcn,q -zxp .40 inch? (The resistivity of copper isk6/ ,xzcz kd-qq ,-npmgqjw3 * $1.68 \times 10^{-8} \; \Omega \cdot m$.)

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  
  What is the resistance of a circular rod 1.0 d3ysu n6ex4 mxp+9 p8fcm in diameter and 45 m long, if the resistifsy 8ppxmdu+e946x n 3vity is $1.4 \times 10^{-8} \; \Omega \cdot m$?

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  
  What length of copper wip/bg 4t *uth3 m.kqsg,re (resistivity $1.68 \times 10^{-8} \; \Omega \cdot m$) of diameter 0.15 mm is needed for a total resistance of $15 \; \Omega$?

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  
  A 120-m long copper wire (res , k3t:2w)0;az qmuio3wa igudistivity $1.68 \times 10^{-8} \; \Omega \cdot m$) has resistance $6.0 \; \Omega$. What is the diameter of the wire?

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  
  A 1.5-cm square rod, 4.0 m long, measures 0.040 ohsyg u48xe4 ;/o kqk 4c9hkjec0nk7,gw ms. What is its resistivity?

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  
  Calculate the current throulgv+wtmkunu.y 291,ws+:oj xs*w(w wgh a 10.0-m long 22 gauge (the radius is 0.321 mm) nichrome w 21y ngw sjw(kx:t +ol*u m.+,uwwv9wsire if it is connected to a 12.0-V battery. (The resistivity of nichrome is $100 \times 10^{-8} \; \Omega \cdot m$.)

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  
  A heavy bus bar is 20 cm long and of rectangular cross-sectioybw d8ippdmc wj6n 947/pm0 ,jn, 1.0 cm x 2.0 cm. What is the voltage drop along its length when it carries 4000 A? (The resistivi,4y6n7p p8w id9j pmj bd/cmw0ty of copper is $1.68 \times 10^{-8} \Omega \cdot m$)

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  
  A 1.0-m length of nichrome wire has a radius of 0.50 mm ane7o)cc4 oa,s3o9zy jd,m bk 3l.ie( hed a resistivity of $100 \times 10^{-8} \; \Omega \cdot m$. If the wire carries a current of 0.50 A, what is the voltage across the wire?

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  
  A 1.0-mm diameter copu enzc3 ;ejhx7. 4d5i g8qqbz)per wire (resistivity $1.68 \times 10^{-8} \; \Omega \cdot m$) carries a current of 15 A. What is the potential difference between two points 100 m apart?

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 carbon resistor has a 01ya f h*cp0z.; dui qlaoz6x(resistance of $18 \Omega$ at a temperature of $20 ^{\circ}C$. What is its resistance at a temperature of $120 ^{\circ}C$? (The temperature coefficient of resistivity for carbon is $-5.0 \times 10^{-4} /^{\circ}C$.)

参考答案:    
本习题练习题目来源于51fly国际课程 (https://51fly.win)，学生可刷题练习，扫右侧二维码或加微信xxxxxxxxxx，获取更多资料
教师可以抽题组卷或一键复制本试卷，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
53#
 
单选题 ( 1.0 分) 切至整卷模式 搜藏此题  
  The temperature coefficient of resistivity of pl.-cknx28,ezkt )r6)vnkm z pgatinum is $3.9 \times 10^{-3} /^{\circ}C$. If a platinum wire has a resistance of R at room temperature ($23 ^{\circ}C$), to what temperature must it be heated in order to double its resistance to 2R?

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  
  A platinum wire is used to determine the melting point of indium. The resistan6muylhew; m(*d 2bf 1mf -2qdlce of the platinum wimfey2m dld h*2b (w1u;l6-fqm re is $2.000 \; \Omega$ at $20 ^{\circ}C$ and increases to $3.072 \; \Omega$ as indium starts to melt. What is the melting point of indium? (The temperature coefficient of resistivity for platinum is $3.9 \times 10^{-3} /^{\circ}C$.)

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  
  5.00 A is flowing throughl)f- h,uhl;r:lmfr g4.m2pf5e wq4qh an $10.0 \; \Omega$ resistor. How much power is being dissipated?

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  
  A 110-V hair dryer is rated + w lz83pvi:;rm()ixqgv;sl dat 1200 W. What current will it draw?

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  
  A 150-W light bulb running on 110 V draws how much curr* lp mm(fgc n8.ckhp89sw 1z;rent?

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  
  What is the nominal resistance of a 100-W light bulb designed to be used a+hp bn;hn g6 tdvo*o+te18h9in a 120-V circuitabtt8o hn ;+h9*gednop6vh +1?

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  
  A toaster is rated 800 W at 120 V. What is the resistance of its heating elem+wp *wv)(bs mp3iq,tt entbw(*sqm ,t 3vi)+ppw t?

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 200-W resistor is rated adampv02r c/ 8b-o x, zfvw4b7et $1/4 \; \Omega$. What is the maximum current it can draw?

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  
  A 200-W resistor is ratesf +8n ys/h.kt6g,jdvd at $1/4 \; \Omega$. What is the maximum voltage?

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  
  A lamp uses a 150-W bulb. If it is used at 120 co+5v bk9ijz5V, what current does it draw?

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 lamp uses a 150-W bulb. If it is used at 120 V, what is i 7oox.ek-q3)f sc3 7)qducdmv ts resistance?

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 25-W soldering iron runs onzpk17b eug;xz*7dez * 110 V. What is its resistance?

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  
  How much does it cost to operate a 25-W soldering iron for 8.0 hours, iflovszkpkbsalla7111 x)h)3v28a n0z energy coss)lk3 k x)na h2aozav1vz7p1s0b8l1 lts $0.08/kWh?

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  
  How much energy does a 100-W light bulb use in 8.-; md -xzmuamm1(d w8m0 hours?

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  
  A 1500-W heater is connected to a 120-V line f7 iwq; hxfhkm01mxy09or 2.0 hours. How much heat energy is produ q h9k0mih 1;xmw7xy0fced?

参考答案:    
本习题练习题目来源于51fly国际课程 (https://51fly.win)，学生可刷题练习，扫右侧二维码或加微信xxxxxxxxxx，获取更多资料
教师可以抽题组卷或一键复制本试卷，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
68#
 
单选题 ( 1.0 分) 切至整卷模式 搜藏此题  
  A battery is rated at 12 V and 1605k fwn. nmad*2zm8h qqp :o-2u A-h. How much energy does the battery store?.2 : nf dw-8monqu5pa*z2hmkq

参考答案:    
本习题练习题目来源于51fly国际课程 (https://51fly.win)，学生可刷题练习，扫右侧二维码或加微信xxxxxxxxxx，获取更多资料
教师可以抽题组卷或一键复制本试卷，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  
  How much energy does a 25hk. sslovfj32x q,m32-W soldering iron use in 8.0 hours?

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 100-W driveway light bulb is on 10 hourstot/*e92oj wk per day. Assuming the power company chargesotokt /9j2 we* 10 cents for each kilowatt-hour of electricity used, estimate the annual cost to operate the bulb.

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  
  A 400-W computer (computer plus monitor) is*h ihfu+o.)u a turned on 8.0 hours per day. If electricity costs 10 cents per kWh, how much does it cost to run th io*auufh.)+ he computer annually?

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 monthly (30 days) electric bill included the cost of;ko6hyu+0nqg t 2*xsg running a central air-conditioning unit for 2.0 hr/day at 5000 W, and a series connection of ten 60 W light bulbs for 5.0 hr/day. How much did these items contribute to the cost of the monthly electric bill if els6xk;qh 2o0 +g*g tynuectricity costs 8.0 cents per kWh?

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  
  The heating element in an electri-1q whewk.mqgx5 ezcc z6ab:kgh0vvy 80(, q6 c drier operates on 240 V and generates heat at the rate of 2.1 kW. The heating element shorts out and, in repairing it, the owner shortk6 ,1v hecyb.qxg hw 80zqg 6-wva0kc z(5m:eqens the Nichrome wire by 10%. (Assume the temperature is unchanged. In reality, the resistivity of the wire will depend on its temperature.) What effect will the repair have on the power dissipated in the heating element?

参考答案:    
本习题练习题目来源于51fly国际课程 (https://51fly.win)，学生可刷题练习，扫右侧二维码或加微信xxxxxxxxxx，获取更多资料
教师可以抽题组卷或一键复制本试卷，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
74#
 
单选题 ( 1.0 分) 切至整卷模式 搜藏此题  
  14 A of current flows throug2rf:+56jh tyatgwo +dh $8.0 \; \Omega$ resistor for 24 hours. How much does this cost if energy costs $0.09/kWh?

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 9.0-V battery costs dftx 6/yjw5,3 etyq c0$1.49, and will run a portable CD player for 6.0 hours. Suppose the battery supplies a current of 25 mA to the player. What is the cost of energy in dollars per kWh?

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 motor that can do work at then:nnlw6b t,t):uuhrvzg *z27 b q8ys2 rate of 2.0 hp has 60% efficiency. How much currev),n2st bzyr2u* t uw ghlq:n 67:nzb8nt does it draw from a 120-V line? ($1 \; hp = 746 \; W$)

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  
  A 500-W device is connected to a 120-V ac power source. What rms cvldkr*6 b8i,4kk (-w *gop2fzqj wv-eurrent flows qk,6ez p dgk fbw**r(l-2iovkwv-48 jthrough this device?

参考答案:    
本习题练习题目来源于51fly国际课程 (https://51fly.win)，学生可刷题练习，扫右侧二维码或加微信xxxxxxxxxx，获取更多资料
教师可以抽题组卷或一键复制本试卷，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 500-W device is connected to a 120-Vo/wol9g8e 2-alg- zxu ac power source. What peak current flows -o/x e9lwgg8o2 z lua-through this device?

参考答案:    
本习题练习题目来源于51fly国际课程 (https://51fly.win)，学生可刷题练习，扫右侧二维码或加微信xxxxxxxxxx，获取更多资料
教师可以抽题组卷或一键复制本试卷，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
79#
 
单选题 ( 1.0 分) 切至整卷模式 搜藏此题  
  A 500-W device is connected to a 120-V ac power source. 4o bj;eha. x7zWhat is the peak voltage across t47e.;hoxb jza his device?

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  
  The diameter of a copper wire is 0.081 inch. The maximum safe curren 8syrs x302wfpt it can carry (in order to prevent fire danger in building construction) is 20 A. At th83s frw0s2ypx is current, what is the drift velocity of the electrons? (The number of electron carriers in one cubic centimeter of copper is $8.5 \times 10^{22}$.)

参考答案:    
  • 姓名:游客(未登录)
    •
    总分:80分 及格:48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 80 道题

    试卷内容到此结束!   © 2025 51fly国际课程 (https://51fly.win)版权所有

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

    GMT+8, 2025-12-20 11:01 , Processed in 0.397329 second(s), 190 queries , Redis On.