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://autoconfig.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://autoconfig.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 bormwo4t0gv /1 y transforming chemical energy into electrical energy i4omo0/1wt rvg s called 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:    
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skysky1258，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
3#
 
单选题 ( 1.0 分) 切至整卷模式 搜藏此题  
  The total amount of charge tha t/1uz-q/lr c:zz fovc9cqir;f0t4e6t passes through a wire's full cross section at any point per unit of 6fo-1q 4 tv/z qlr9et0: i/ ;czrczucftime 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skysky1258，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 convention current is taken to be the direction th-i m9 , a56lqyrew:gtaat

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  
  A coulomb per second is thehc)4pn89v lh ,m5lvo j,bxnky4n0 wv8 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-hours.tvvz9b74;f 5a d nkc2* ha7mkz" This is a measure of their

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  
  The resistance of a wire is defyj fxz-3ux0*4 to7+ufoc3a hqined 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 wir8dz75 -fbwo ybe 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 obo-hs1vp 9(py:,hru mn

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 lowest resistivi)xvcop8g/4cs ty value?

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  
  Consider two copper wires. u0/ z 6lbv q((hcpkgk)One has twice the length of the other. How do the rev6kpu(c)qzb g0l kh/(sistivities 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 vlt2e s cn2)+sof the other. How do the resis evs2+)lc2 nsttances of these 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 hv: pcbbt9t/jrz2;2x wires. One has twice the cross-sectional area of the other. How do the resistances of these trbc/;px j2vt9 2 tbzh:wo 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 the length and twice the cross-sj dk+43l9 m kwu0mduydo.-j 1pectional area of the other. Ho-m dy3+.l pjk 4mj owuddk91u0w do the resistances 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 doubled and the radius is bzq .dils;z.3doubled. By what factor does the resistance c. qi3 l;z.dszbhange?

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 resistance does a 1.0 cm diameter rod have compa;,2kkquy 3 u hm i1kvm* pzi,iu6s+)sdred to a 2.0 cm diameter rod of the same lv3uuuhipys)6z qm s k,,i1i+mkd k2 ;*ength and made of the same material?

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  
  The resistivity of most commolb btv;bkta2s6 z( h41qbr3j*n metals

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 coef r4t/6 ou63a+ kg+rqtitr5jsrficients of resistivity

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  
  What is 1 W equivalent t6,1eq:y b 5nacskqb.ho?

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 equivalent kz n/caf*+tx*p4 f.dk 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 constabx(xqf 7cj(po7ifh)p l.n*,u nt voltage circuit is doubled, the power dissipated by that circuit will.x uo)7(bx*pln qffc,(ip j7h

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 constant resistan3(g5k;u fhn sr,-sm)asm jyg.ce is doubled, the power dissipated;ms k-ms n . g(,jf)hg3ryus5a 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 withllvjlbtwn7dipeeh0je,;t37e9h. pm a ,/ r40 constant current flowing is doubled, the power dissipated/ mje;n0alp vre97l 0j i elet h,,d3.hb74ptw by 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 circuitmo/4wyiq mp 79 of constant resistance is doubled, the power dissipated by 7qy wmi9m o4p/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 is reduced by 5.0%. By what pe j:iloj0 yv.6grcentage is the p:v6 joyjigl0 .ower 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skysky1258，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 ref,vm8mzlps9)g-k y ,cr erred to 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 each carrying a current of 3.0 A.m0 e8ke 00h8pny8l71f z xckl:pmnz8 s One wire has twice the diameter of the other. The ratio of the drift velocity in th7 0k8zyz:mlp n8pxf ech0smlk1ne8 80e smaller diameter wire to that in the larger diameter wire is

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skysky1258，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
29#
 
单选题 ( 1.0 分) 切至整卷模式 搜藏此题  
  Materials in which the ef;syxc5w+ vmzs6, 8 presistivity becomes essentially zero at very low temperatures are referred to 58smp 6e +xc;,wz fyvsas

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  
  What current is flowing if 0.67 C of charge 6 (gz*elne.xlcldxc-qw2/e* pdi )5npass 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 aj4:xy;x q,vv bpparatus in 2.0 min. What is the average vbj4q:vx y x,;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 pass by a point in 10 s7zg:er+zp+43o s gz wf 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:    
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skysky1258，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
34#
 
单选题 ( 1.0 分) 切至整卷模式 搜藏此题  
  What current is flowiylq 3: 3 syd.ysfendj/m+e-6 qng if $4.0 \times 10^{16} \; electrons$ 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 l( 5ql: hu0j u6j blag8;d5aytqeft on for 10 min. What is the net number of electrons that havelg(t65a5djybu h08qqj ;a:ul passed through the 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skysky1258，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,omip p si-7c7jeu4y5 v-.y af- it is desired to deposit 40 mg of silver on a metal part by using a current of 2.0 A. How long must the current be allowj77fs oc-e iypvm- iy- 4u.pa5ed 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 requireskc-yh:qk2 6 le 69cak)i 8sdfd to cause 4.00 A to flow through a resistance of 33yhfsk a-68:2qs 9dke)ic lk6c0 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 across a 5.0-W resistor if the current through it is 5.0i4bc-7hnk c-x 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 current w n/cx;ihq;eeo;pwn,ga0g7f 0 ill 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 1.4nj.an2jmqy998 dqy9fr(4 swja mfh: 30 A of current. What is its resistance?9y q2 8mn far399m(j:jjyfsqhan4d .w

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  
  A 12-V battery is connected psz+q*( s v-tak.y:8hhrzwi2 to a 100-W resistor. How many electrons flow through the wire*2 s: -y8.qzhazt (sr phkvw+i 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 wire8 +lsdiv4 3lzj of diameter 0.40 inch? (The resistivity of copi3d4sz8v+lj lper is $1.68 \times 10^{-8} \; \Omega \cdot m$.)

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 rodjxqaq/dn2 lvx-w,9i( gb6f7 e 1.0 cm in diameter and 45 m long, if the res6/xi(9vnaeqj-dxw fbq27 l,gistivity 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 wire (resistifn *qhe76 ita qg3+rb:vity $1.68 \times 10^{-8} \; \Omega \cdot m$) of diameter 0.15 mm is needed for a total resistance of $15 \; \Omega$?

参考答案:    
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skysky1258，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
46#
 
单选题 ( 1.0 分) 切至整卷模式 搜藏此题  
  A 120-m long copper wire (resistivity v c,lsk310ic04vekz mom8iv8 $1.68 \times 10^{-8} \; \Omega \cdot m$) has resistance $6.0 \; \Omega$. What is the diameter of the wire?

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skysky1258，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
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, maevpv,1bh,y 6 z)y eknsmst7u.g 7)( deasures 0.040 ohms. 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 ( pzrae* gdxd-;+tsw4)+ 5uw;eebk yuthrough a 10.0-m long 22 gauge (the radius is 0.321 mm) nichrome wire if it is connected to a 12.0-V bae duu(+ *;- ywede+r 4xgas)k5w ;pbtzttery. (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 1rs+;; u) bikd*ubqr scm long and of rectangular cross-section, 1.0 cm x 2.0 cm. Wh;+sir ;u*u)1 dbqkbsrat is the voltage drop along its length when it carries 4000 A? (The resistivity 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 and a resistio:g d42r kgu-wsip(p k+c qz29vity 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:    
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skysky1258，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
51#
 
单选题 ( 1.0 分) 切至整卷模式 搜藏此题  
  A 1.0-mm diameter copper wire (resistivity nt 1aqp/ojmg+nd*d (;$1.68 \times 10^{-8} \; \Omega \cdot m$) 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 zoy2(ir yp8ccd14:q s a 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:    
标记此题
53#
 
单选题 ( 1.0 分) 切至整卷模式 搜藏此题  
  The temperature coefficient ok9szlb )cmxzcp92 +8tf resistivity of platinum 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 useu 4n2s0l 4;l6hmtlbrq+m(k r zd to determine the melting point of indium. The resistance of sm 0r4 ;2m+k u6brlll4nt(zqhthe platinum wire 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 through m1ebxsnl- 8k,g a4- 3nb h+hahan $10.0 \; \Omega$ 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 at 1200 W. What current will it dra 4o5fk- wk-wafw?

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 r14 9aal mgcwfkqk,19V draws how much current?

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skysky1258，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
58#
 
单选题 ( 1.0 分) 切至整卷模式 搜藏此题  
  What is the nominal resistance -zez hx p28*yhof a 100-W light bulb designed to be used in a 120-ex*8zy2hzp-h V circuit?

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*z05 kqi:kls iv* efst9,(toc heating elementcl* fv:e is(5*k z, st90qikto?

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skysky1258，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
60#
 
单选题 ( 1.0 分) 切至整卷模式 搜藏此题  
  A 200-W resistor is rated ahik .p1( cm8sk/g4cdat $1/4 \; \Omega$. 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 rated at 6wbio1ej6o ())i lfmn$1/4 \; \Omega$. 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. I5q b m,w9iks,sf it is used at 120 V, 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 itsiyk;gg9 rrgk .,,fhn. 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 on 110 V. What is its reswa t5f/ym*3uoistance?

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skysky1258，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
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*qwn:( a vp )4pxnw;na-W soldering iron for 8.0 hours, if energy cosxan)4*q vp:wpnwa ;n( ts $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 10ga08*mf 0v izh0-W light bulb use in 8.0 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 for 2.0 houq/3 *:g/ogg9 yyteitnrs. How much heat energy t in yqg*/o/y: 9tgeg3is produced?

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  
  A battery is rated at 12 V hc(h m9-k4 5eptdafw2 and 160 A-h. How much energy does the battery store? (f4 25kwmh9d pchta-e

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  
  How much energy does a 25-x/ey( w3qu5tph7k e f +kb0:d ejy+hj0W 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 1gi0r(gxq z pt4j fm**ibg-c290 hours per day. Assuming the power company charges 10 cents for each kilowatt-hour of electricity used, estimate the annual cost to op xct q0 *g prigmbiz92g*4(-fjerate 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 pl t / e7cfydk6s;3ss9nxus monitor) is turned on 8.0 hours per day. If electnftc 3sdk9s;6e7s y/xricity costs 10 cents per kWh, how much does it cost to run the 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 ofck3eix.4 )6lo mwmrr/ 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 tw .k3)x/ rei m6lcrom4he monthly electric bill if electricity 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 electric drier operates on 240 V and ugjg8*(sn6;b26bv 8kgwd pxpgenerates heat at the rate of 2.1 kW. The heating element shorts out and, in repairing it, the owner shortens the Nichrome wire by 10%. (Assume the temperature is unchanged. In xwju6(dp8*k g8sv 6p;b n2bgg 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:    
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 throughnqwb csmjocf0m7; 515 $8.0 \; \Omega$ 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 costbns yw+ : 1ze)8cr(;:kuiqkxhs $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 the rate of 2.8qiom8 t :pww r-ps70u0 hp has 60% efficiency. How much current does it draw from a 120-w-:m8sroiq t7 pwup80V 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 120woe.++l jxoe:k( qkf.-V ac power source. What rms current flows through this + +xlejokko: efq(..w device?

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 500-W device is connected to a 120-V ac power source. What peak current :)x/,mn7i,l0qg ow.hwc xst aflows through this devimng t s0/o,wq h:xc,x).iwl7ace?

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  
  A 500-W device is connected to a 81 yvjgu/bu6c)nx(y k 120-V ac power source. What is the peak voltage acxu/ gkc yju6y 1n8v(b)ross this 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 so;v56d v+ h abm3-sorkafe current it can carry (in order to prevent fire danger in build- o5abkrd3hmovs;v 6+ing construction) is 20 A. At this 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:    
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skysky1258，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
  • 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
    本平台(https://autoconfig.51fly.win/)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

    试卷内容到此结束!   © 2026 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, 2026-4-17 09:58 , Processed in 0.565192 second(s), 190 queries , Redis On.