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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://autodiscover.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://autodiscover.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

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1#
 
单选题 ( 1.0 分) 切至整卷模式 搜藏此题  
  A device that produces electricity by cubgx5j9ez )j 8rim h32:s(m (hnbfo1transforming chemical energy into electrical energy is callo:fjch hmr(exz8 bmjsgb (i2n 135)u9ed a

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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
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2#
 
单选题 ( 1.0 分) 切至整卷模式 搜藏此题  
  A car battery

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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 crossx )l ) e+ckmdh(e8z.gdz-f o8h section at any point per unit of time is referred to h ( -d mdez8gek+. lxhoz8f))cas

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4#
 
单选题 ( 1.0 分) 切至整卷模式 搜藏此题  
  The direction of convention current is taken/ ;5f k(gln9py j2b*,j zgifcv to be the direction that

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5#
 
单选题 ( 1.0 分) 切至整卷模式 搜藏此题  
  A coulomb per second is th 5s q+axf)e(+or*f f4b8xl aane same as

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6#
 
单选题 ( 1.0 分) 切至整卷模式 搜藏此题  
  Car batteries are rated in "amp-hours." T bri bqoymw*:+/v n3,1 4murrhlk b8 ff84cv,jhis is a measure of their

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7#
 
单选题 ( 1.0 分) 切至整卷模式 搜藏此题  
  The resistance of a wire is defines nj 88etnkop o89y1dixz9, z7d as

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8#
 
单选题 ( 1.0 分) 切至整卷模式 搜藏此题  
  What is $1 \; \Omega$ equivalent to?

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9#
 
单选题 ( 1.0 分) 切至整卷模式 搜藏此题  
  The resistance of a wire i2 desjrn 72,e9pkno*duxn )m/ ak-h q6s

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10#
 
单选题 ( 1.0 分) 切至整卷模式 搜藏此题  
  The resistivity of a wire depe8-fhldf omshyjpg xj/ f))f n mg5-8ft/4px,+nds on

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11#
 
单选题 ( 1.0 分) 切至整卷模式 搜藏此题  
  Which conducting material has the lowest resistiviec b7s.c3b32wmpwk8lh,q3fpz*ho n 5ty value?

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12#
 
单选题 ( 1.0 分) 切至整卷模式 搜藏此题  
  Consider two copper wires. One has twice the lev d-0ax9xja9 d. 1eylkngth of the other. How do the resistivities of thed1.0eayxv -9aj kd9xlse two wires compare?

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13#
 
单选题 ( 1.0 分) 切至整卷模式 搜藏此题  
  Consider two copper wire0c/0l2qc5odwj j zl. ns. One has twice the length of the other. How do the resistances of these two wires jwlqcdoz2jlnc5/0 . 0 compare?

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14#
 
单选题 ( 1.0 分) 切至整卷模式 搜藏此题  
  Consider two copper wires. One has tl324pf co7sx6 dmd-ldwice the cross-sectional area of the other. How do the resistancp dsd2 -o46cf37xllmd es of these two wires compare?

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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 o3ef xgp -hv:-length and twice the cross-sectional area of thx hv-og-3:fepe other. How do the resistances of these two wires compare?

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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
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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 doubled.sr g 058.he:i qqqry eu1zv7b+ By what factor does the resistance +zveu 0 re7r.ybghsqq iq:185change?

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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 compared to a 2.0 cm dxk:um tr /3 y:s9w60gad:tz2 vr:ajmziameter rod of the same length and made of the same mr/a:mutrzsx:d2: 9zg twv6a :kyj 03 material?

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18#
 
单选题 ( 1.0 分) 切至整卷模式 搜藏此题  
  The resistivity of most comm7dkwj7z3 m9 +w si3er)oex/f fon metals

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19#
 
单选题 ( 1.0 分) 切至整卷模式 搜藏此题  
  Negative temperature coefficients kgg8k/bm9b2 z of resistivity

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20#
 
单选题 ( 1.0 分) 切至整卷模式 搜藏此题  
  What is 1 W equivalent to? 3 4oi;:qmlc8ccaazq 1

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21#
 
单选题 ( 1.0 分) 切至整卷模式 搜藏此题  
  A kilowatt-hour is equivalenw/i8d57ck. z t 2r8jp ejpqn-wt to

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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 dissipated) u rnm*whq(n(;b- rzy by that ci;- yruh wnnr(z(q *)mbrcuit will

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23#
 
单选题 ( 1.0 分) 切至整卷模式 搜藏此题  
  If the voltage across af:fd+f n3ma-qy5w 8 h3cynr. ltp x96a circuit of constant resistance is doubled, the power dissipated by tc5r nhad nf-9y:8qyt 3.l6pw 3+x famfhat circuit will

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24#
 
单选题 ( 1.0 分) 切至整卷模式 搜藏此题  
  If the resistance in a cire lhhv vr ix1(g 3f/,zon)5)uncuit with constant current flowing is doubled, the power dissipaifn13ze u)/ n,xgv( 5h rlho)vted by that circuit will

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25#
 
单选题 ( 1.0 分) 切至整卷模式 搜藏此题  
  If the current flowing through a circuit of constant resistance is do/gpxg, d0n fd8a*vsapgv0 )k7 ubled, the power dissipated by n*d)g0 pdg8ka7agpf /,xv0s vthat circuit will

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26#
 
单选题 ( 1.0 分) 切至整卷模式 搜藏此题  
  During a power demand, the voltage output (4rj, nq b-lnmx,s gkw2dx:s.dxfr/* is reduced by 5.0%. By what percentage is th*s(kfd -j,l x, s. 4/gm2 :wqxdrbrnnxe power on a resistor affected?

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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 to asdw.f ccb0i5:d z (fc,q

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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. j:ves7v.j5 qcupl/ .y One wire has twice the diameter of the other. The ratio of the druq. vpe7 cvy/5.s:ljjift velocity in the smaller diameter wire to that in the larger diameter wire is

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29#
 
单选题 ( 1.0 分) 切至整卷模式 搜藏此题  
  Materials in which the resistivig v*8;(nug( awii3wzbty becomes essentially zero at very low temperatures are referred towiiuva bz(8g w(;g*3n as

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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 pass a poin-xzp8 :u5k dof c;)zsw,kp 7rq7 lhj7gt in 0.30 s?

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31#
 
单选题 ( 1.0 分) 切至整卷模式 搜藏此题  
  A charge of 12 C passe8.n+n 5f dbqxu q7lo fg8d4p8ss through an electroplating apparatus in 2.0 min. What is the aver45.8l 7dbqf nnd fsux gq8o8p+age current?

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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 s for the curren)h.( lj zuf4jnt to be 0.50 A?

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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?

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34#
 
单选题 ( 1.0 分) 切至整卷模式 搜藏此题  
  What current is flowin8 lbbpy 3l+ ggj8d .9wujcm57( xjjoa(g if $4.0 \times 10^{16} \; electrons$ pass a point in 0.50 s?

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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?

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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 cujff,pl p()i)9a u5dlqyc)2k crrent, has been left on for 10 min. What i) 5pi2c(ukf )dl )j9,qalfp ycs the net number of electrons that have passed through the coffee maker?

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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
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37#
 
单选题 ( 1.0 分) 切至整卷模式 搜藏此题  
  In an electroplating process, it ivam a;f/ m.4ypvmg(; hs 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 allowed to run to deposit this much silver? (The silver ions are singly charged, and the atomic weight of silver is 108;vga/ mm(p;am hvy. f4.)

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38#
 
单选题 ( 1.0 分) 切至整卷模式 搜藏此题  
  What potential difference is required to cause 4.00 A to flow throug*i k:iblk,ar lv2a1rbw g;b2: h a resistance of 31lk 2;,bb bilr ki*a:v:2argw 30 W?

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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 c b/ d;d a m*162r3tserr)y0dqhnb+fjx 8sjy6furrent through it is 5.0 A?

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40#
 
单选题 ( 1.0 分) 切至整卷模式 搜藏此题  
  A 4000-W resistor is xn5 nu7-d998 cdiabgc4h 2jolt ly) 1cconnected across 220 V. What current will flow?

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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 1.40 A of current. What is its resistance :jb( /aqtusf7h.nra.tahs.afqb/7u.:n( j r?

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42#
 
单选题 ( 1.0 分) 切至整卷模式 搜藏此题  
  A 12-V battery is connected ttpik dlnb6yj4.d+b;pb 08 + jro a 100-W resistor. How many electrons flow through tjp6j yb .bdknp+dbi+8;r40l the wire in
1.0 min?

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43#
 
单选题 ( 1.0 分) 切至整卷模式 搜藏此题  
  What is the resistance of0pmcbz(4ho) zn0on ,cp7 t 1ex 1.0 m copper wire of diameter 0.40 inch? (The resistivity of copm(c,0 nh)o 70 c1o4zbnt pzxpeper is $1.68 \times 10^{-8} \; \Omega \cdot m$.)

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44#
 
单选题 ( 1.0 分) 切至整卷模式 搜藏此题  
  What is the resistance of a cibafqmr3 +5f 59xjk3bwn- h jm-rcular rod 1.0 cm in diameter and 45 m long, if the5 axrf93kwqbm -m-njj+b3 h5f resistivity is $1.4 \times 10^{-8} \; \Omega \cdot m$?

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45#
 
单选题 ( 1.0 分) 切至整卷模式 搜藏此题  
  What length of copper wire (resistivity9 y8m,zteelf5wwvr )3 $1.68 \times 10^{-8} \; \Omega \cdot m$) of diameter 0.15 mm is needed for a total resistance of $15 \; \Omega$?

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46#
 
单选题 ( 1.0 分) 切至整卷模式 搜藏此题  
  A 120-m long copper wire (resis nh*9sv,v4 d 0f3yjswctivity $1.68 \times 10^{-8} \; \Omega \cdot m$) has resistance $6.0 \; \Omega$. What is the diameter of the wire?

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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 ohms. wqrq)3 j a)j7c tdxm*esc4(0kWhat is its resistivity?

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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
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48#
 
单选题 ( 1.0 分) 切至整卷模式 搜藏此题  
  Calculate the current through a 10.0-m long 22 gaugbh.e5fajw9k a *:vm.w0) iku ce (the radius is 0.321 mm) nichroh.kuk0* fa) ec:5 9ivwja.m wbme wire if it is connected to a 12.0-V battery. (The resistivity of nichrome is $100 \times 10^{-8} \; \Omega \cdot m$.)

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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-section, 1.0 cm x 2.0 cms4spvdy 2c1 gx 5 nup n18,wa:+3udizo. What is the voltage drop along itov,w1:4ng5 cuu+a z1pyi ps8nxs 32dds length when it carries 4000 A? (The resistivity of copper is $1.68 \times 10^{-8} \Omega \cdot m$)

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50#
 
单选题 ( 1.0 分) 切至整卷模式 搜藏此题  
  A 1.0-m length of nichrome wi7),wb hi*hxf ) eqjto-re has a radius of 0.50 mm and 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?

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51#
 
单选题 ( 1.0 分) 切至整卷模式 搜藏此题  
  A 1.0-mm diameter cop:plr ,t/4 ht)pjv hzjm )6qkor()e4 lwa6;unaper 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?

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52#
 
单选题 ( 1.0 分) 切至整卷模式 搜藏此题  
  A carbon resistor has a rb5837 dqz)ogx3r*a bxdv x88 m58d5skzx jwppesistance 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 $-5.0 \times 10^{-4} /^{\circ}C$.)

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53#
 
单选题 ( 1.0 分) 切至整卷模式 搜藏此题  
  The temperature coefficient of resistivitfjjr 3s 3r5,jpy 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?

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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 poojqp bqi;v0/jg g. -,u(gsw5uint of indium. The resistance of p i q0s; jqvub,g(jg./u5 go-wthe 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 $3.9 \times 10^{-3} /^{\circ}C$.)

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55#
 
单选题 ( 1.0 分) 切至整卷模式 搜藏此题  
  5.00 A is flowing thr ct9gm0*),l+6hww dt lsrt: wlough an $10.0 \; \Omega$ resistor. How much power is being dissipated?

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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 49cr6b)erum iu9 li6pdraw?

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57#
 
单选题 ( 1.0 分) 切至整卷模式 搜藏此题  
  A 150-W light bulb runninx 6(lgrck:z*yg on 110 V draws how much current?

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58#
 
单选题 ( 1.0 分) 切至整卷模式 搜藏此题  
  What is the nominal resistance oho mn2ay- 5yj*2szi 1hf a 100-W light bulb designed to be used in a 120-V cyo-hyj1*2izmh s5 an2 ircuit?

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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 hea:rt k+ki 7hc-+ssbz 9qting element?++ 9czh7tsiq - srk:bk

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60#
 
单选题 ( 1.0 分) 切至整卷模式 搜藏此题  
  A 200-W resistor is rated atqh(e) 7bgp-g t $1/4 \; \Omega$. What is the maximum current it can draw?

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61#
 
单选题 ( 1.0 分) 切至整卷模式 搜藏此题  
  A 200-W resistor is rauc7tb:q2+z o g *a )l2*ayzs-bfhdk r1ted at $1/4 \; \Omega$. What is the maximum voltage?

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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 V, what current doesww3 u 21bda(td it draw?

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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 its resistancb*c1m d8 j0tlje?

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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.dzi c+lp,/qh)z 3lp 6p What is its resistance?

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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 iroctk s/s w)*k6zn for 8.0 hours, if energy cost ss6czkk/w *)ts $0.08/kWh?

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66#
 
单选题 ( 1.0 分) 切至整卷模式 搜藏此题  
  How much energy does a 100-W lig3).yy+b4bdykpv8x- ljbu r l, ht bulb use in 8.0 hours?

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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 hours. How much h(nt-nl *l3eonhd4h o5bl7 q/reat energn end5 3-rq4tl/7noolh*h(lby is produced?

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68#
 
单选题 ( 1.0 分) 切至整卷模式 搜藏此题  
  A battery is rated at 1(khq; ) 5s pubg-rc)x cp;+du2b- stnn2 V and 160 A-h. How much energy does the battery store?;)rdhx -n( s2gpnp5-tc )qsu;bc ubk+

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69#
 
单选题 ( 1.0 分) 切至整卷模式 搜藏此题  
  How much energy does a 25-W stv.,u zjo0d1 ioldering iron use in 8.0 hours?

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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 hours per day. Assurdtx:ps inne9 (vn;*:ming the power company charges 10 cents for each kilowatt-hour of electricity used, estimate the annual nt*r ns:i;n:x dve(9pcost to operate the bulb.

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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 turned on 8.0 hj7/c ow29z)hcry w1auyt/c; mours per day. If electricity costs 10 cents per kW9w7;m/r)a tz cu1h/cyywoc2 jh, how much does it cost to run the computer annually?

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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 running a c0cmsq0(*(gzp 21r3gthsfrn rentral air-conditioning unit for 2.0 hr/day at 5000 W, and a series connection of ten 60 W light bulbs g1((tr3cnmp0 2 0hgs*rrfzqsfor 5.0 hr/day. How much did these items contribute to the cost of the monthly electric bill if electricity costs 8.0 cents per kWh?

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73#
 
单选题 ( 1.0 分) 切至整卷模式 搜藏此题  
  The heating element in an elec5qjosahx6eo:oysn2 +u/ ol ,osd6.* w tric 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 shortens the Nichrome wire by 10%. (Assume the temperature is unchanged. In realitoodo6 qo:s *2lx. o6un/y,+hejas 5s wy, the resistivity of the wire will depend on its temperature.) What effect will the repair have on the power dissipated in the heating element?

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74#
 
单选题 ( 1.0 分) 切至整卷模式 搜藏此题  
  14 A of current flow.p(v p, (k srch)4ojhoz nea9*s through $8.0 \; \Omega$ resistor for 24 hours. How much does this cost if energy costs $0.09/kWh?

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75#
 
单选题 ( 1.0 分) 切至整卷模式 搜藏此题  
  A 9.0-V battery costs /et 5og 5b 3)o nfk6gle0ohyk9$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?

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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 2.0 hp has 60% efficiency. e:b dqy )+gwx 1xmn6)x How much current does it dr)yed:1)mxg q 6nwx+bxaw from a 120-V line? ($1 \; hp = 746 \; W$)

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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 12azr,65cs yai7iw sf zmb k4n1yi)6.t 60-V ac power source. What rms current flows through thisr 5)y66cissty,a 7mkia4i.fwzn1 bz6 device?

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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:7k-.gc w4+o.e p f aew,3oymtwqb:bp peak current flows thw m p.4toq:o+f,k w.egew7y3 cbapb:-rough this device?

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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. What is the8m. w*bdfuh ld+ 3 bjn*cbt00n peak voltage across this device?m * nbhd 80cwt30*ubfdnj.+lb

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80#
 
单选题 ( 1.0 分) 切至整卷模式 搜藏此题  
  The diameter of a coip h23*2 -k0yekqvgq ucdx*p :pper wire is 0.081 inch. The maximum safe current it can carry (in order to prevent fire danger in building construction) is 20 A. At this current, what is the drift velocity of the electrons? (The number of electron c2 gvcdxpy3 h p2*i0*q q-kkue:arriers in one cubic centimeter of copper is $8.5 \times 10^{22}$.)

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