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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://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

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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 transforming chemical energy into elyackdm lcl1 :y.3x).yectrical energy kcyxay13l: m dl). cy.is called a

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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 cross sectvvqw6h ll.h ;7h7 tlm*ion at any point per unit h6llmt 7lq;h 7*v vwh.of time is referred to as

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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 to be the direction tha t5t )ycx0htcsi5sa trr8)f1*t

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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 the urf. t piz g21dvn688xsame 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." This is a measure 5q(v 6xxrmw 0y3uivrdm 1*df6of 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 de2xk) -ghm; r:on,qi sffined 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 3( b,2s fsfychoh-;ag is

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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 dependsy0iblq:nfn +* 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 resif 3o:4hp,e wzky6yar*7 0iu*cf; la-k s n5dtxstivity 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 wicc8mbpn xb3 ))u;kjdu0/ hi.ires. One has twice the length of the other. How do the resistivities of 0xbm.uiji k b8cc)u3 );pn h/dthese 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 wires. One has twice t e+5ylua;wtla1-f ax,he length of the other. How do the resistances of these two wires clalt5e;u-,a fy+1waxompare?

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14#
 
单选题 ( 1.0 分) 切至整卷模式 搜藏此题  
  Consider two copper wire :yt k:3qv1.x . jivo(cynk;pns. One has twice the cross-sectional area of the other. How do the resistances of these two wires cot .jvk3i: c1vqnxpy; (on:.ykmpare?

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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 length and twilwq: uqy 7);obce the cross-sectional area of the o7y:;wuqoq ) blther. How do the resistances of these two wires compare?

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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. By what facteld-5ttdy;ymt :a;4rpi6 ed* or does the resii e e6dad4-5r;m; lt*:ptyd tystance change?

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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 coo+(x5uymca1 hn2cas+wym 8e 3 6np9hjmpared to a 2.0 cm diameter rod of the same length and made of the yhjn2pyc8 69xu ++a 1mewas 3nh5com(same 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 common fg3w)ximkz 8,n i9rv8metals

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19#
 
单选题 ( 1.0 分) 切至整卷模式 搜藏此题  
  Negative temperature coefficients of resi j8p4 :0 75ef5fui;jwuhoergastivity

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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 tt4v xr80zn.e (ogd c*po?

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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 equivalep56gw)icmn1lujsk;gc7w *gp:t2k5hnt 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 diei xgr:ly4p+8ssipated by that circuit egl+r p:84 xyiwill

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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 a circuit of constant resistance is doubled, the power tz;lgx r2mj19 1k6; ,k svt4siyh3i gsdissipts1mk9hi;;sl2, 14t3 gskzixgy6 vjrated by that 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 ci r-87 .m6nmnoof-a byyrcuit with constant current flowing is doubled, the power dissipated by that circuit r yfmn-.8 oabm7 yn-6owill

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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 resist8r(w l7.s 5sfrb7vmwkf- tnsp.rg ,1gance is doubled, the power dissi-fn rkvsblgw 7r. w sr,gfs.p8t75( m1pated by that 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 is reduced by 5.0%. By what pei02yer82.l-e a /o( p-qss3e keoibzjrcentage is the po s aeo.3(yeriel8ik /pq-sebj-o 2z02wer 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,kllobqnvr :v 9irqn e*: sw2)+gup2. to as

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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 carrying6 .2drw19g se fhtq-yh0acdn- 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 nf cqd.r9-ws t6 dey0 hgh-a12larger 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 resistivity be2 pk)(nvy87vposkovy1* d2bncomes essentially zero at very low temperatures are referre yo2 pnov(*87yvk dnksp21 v)bd to 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 puhjnv gnd7l3f u 97m,ga qje *bt(vd ;j0le-68ass a point 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 passes through an electroplating apparatus in 2.0 min. q1(j4*k niajpWhat is the averagpn (*ji1k4qaje 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 current to be 0.506m/)-xxotbwtlzmr+ t(-ao c)i,2 wsz 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 flowingtq y/tty.ji 8e9; 0kb(gh 9ziy 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 current,u,pbs/r9s( hc9+w cm*ewfzh */gzeu, has been left on for 10 min. What is the net number of electrons that haws9+zwc z /,e9h/b mse(fc*urgu* h,pve passed through the coffee maker?

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37#
 
单选题 ( 1.0 分) 切至整卷模式 搜藏此题  
  In an electroplating procemm4qwrd 10pziuyxse*) 9-+ptg4 w wt (ss, 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 allowed to run to deposit thi i4g14s - pr* )t0+wmwyxwqze(m dtu9ps much silver? (The silver ions are singly charged, and the atomic weight of silver is 108.)

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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 through a r)i4 0 vg/a p1p(b nj*(xsukcjeesistance of 330 W?spjn u c0)v/ga*(p4x1j( ekb i

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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 i3v.cyh x +xb.uf the current 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 connected across 220 V. What current wiwu5,ln2 l; hfffxu9 d1ll 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. W bn00p 6ffq lo.jk :d(iueejj:g1n a suu11h13hat is its resistancejnpn0use06ij q o 1uk:l1( d.u ag3f1bj:1feh?

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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 to a 100-Wcr- 2niph+,gw resistor. How many electrons flow through the wire w+,pg -hincr2in
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 of 1.0 m copper wire of diameter 0.40 inch? 4 8zn4gdk 1hs4ftfxeyz w 8qfx88 f5z1(The resistivity of c8x f8wf1 g8ns z14fq4te5 x y4hfz8dkzopper is $1.68 \times 10^{-8} \; \Omega \cdot m$.)

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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xxxxxxxxxx，获取更多资料
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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 circular rod 1.0 zo *v (rf8xcr6xk7pf4 get:9jcm in diameter and 45 m long, if the resistivity i4x f6e cpkf r7*8ovr:z(9xtjgs $1.4 \times 10^{-8} \; \Omega \cdot m$?

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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 wirnp1v1h p7mvn0 vsy7b(3ef7h ae (resistivity $1.68 \times 10^{-8} \; \Omega \cdot m$) 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 (resisj06 .csn h/ezwtivity $1.68 \times 10^{-8} \; \Omega \cdot m$) 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. What is its resifcfui div9/+4stivity?

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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 rbpo8d i*6t;xt (n.u mlong 22 gauge (the radius is 0.321 mm) nichrome wire if it is connectepdto8n tb(im*; 6xr.ud 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 crf zxva 0un10e2oss-section, 1.0 cm x 2.0 cm. What is the voltage d0af2n1uxe 0zv rop along its 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 wire has a radius of 0.50 mmq./ o y ssc66rb8nvuv8 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 copper wire (resistivity n3 9kt cq+m 8p ixainph* e-9j()o*lxb$1.68 \times 10^{-8} \; \Omega \cdot m$) 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 resistance of 6n8.im*k nxd kn6z0kr$18 \Omega$ 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 coef glq9h82pwi;oyy,*zw ficient of 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?

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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.yaoqjh 9u;* h melting point of indium. The resistance of the platinum wirjh*h9;a qu.oy e 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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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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55#
 
单选题 ( 1.0 分) 切至整卷模式 搜藏此题  
  5.00 A is flowing throu e:yvia*pq3tvfh qp;, f 375qlgh 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 rat ilq9av w*6mw-ed at 1200 W. What current will it draw?

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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 runn-v ph e90kgpe5ing 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 of a 100-W light bulbw rmjxln5u:eq4/ nrub wf/5d-x4 uu 20 designed to be used in a 120-V circuuf2-lu0r/wrum j4 bqw d5x/4:u5 nnxe it?

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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 heating elem./ djsypm3 vq2en syjm 3vdp/.q2t?

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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 rat gc(w .0lv /uwws +vnp9-/mdvred at $1/4 \; \Omega$. 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 rated sy718wby3vxl 15 zbs ;d aukp/p ro8*iat $1/4 \; \Omega$. 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, whauw1jsz6dn8 r va .mk5e 6kn:+zt current does 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,; :yzor+)n e a,:dpfzcao+ ts8iw 5dp2 what is its resistance?

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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 V2n 8gyu mfxyrmt:(qd 28j)jn,. 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 2wm2*2uk slpp*,w8qr 8ju/ tiq5-W soldering iron for 8.0 hours, if energy co l2m q,uiwwj/pp* 28tu r8q*kssts $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 ligi+i9duw2gv e3: con5jv k 9z)sht 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 la bzq;icv(nz ;h -4/puine for 2.0 hours. How much heat energy hpnbzz/cv;-i;4a q(uis 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 12 V and 160 A-h. How much energy does the battery storev3fmn0 6uh+ hr?mr v3h+6n fh0u

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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 25v,k ge 3zg ksk k-l,o98fb1jz/mvhk:)-W soldering 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 da3anvd2n71,yg na5k f+oqcqq- y. Assuming the power company charges 10 cents for each kilowatt-hour of electricity used, estimate the ann5ya-k cfa gqn3dv+7nq1 no2q, ual cost 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 ssz ajj70b9q f:3 )zm4+jqsovmonitor) is turned on 8.0 hours per day. If electricity costs 10 cs9)3: zj+qsf0bom7 jvz jas 4qents per kWh, 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 ttp; ,w.7xxgxnsl: vzkz;m :+ bill included the cost of 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 elect : .:sp,k ;xl+xvgt7mzxzn tw;ricity 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 electric drier operates on 240 V and generates hegr6 .w2-zn kdkat 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 reality, the resistivity of the wire will depend on n kzkdw6r .-2gits 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 flows throu 0oz 29nem e)2kau0tlwgh $8.0 \; \Omega$ 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 bkiz4 x3kj9vwty )ui 8,rmr4*$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.a(gyufi:wy2i( bme jd// ; y4s0 hp has 60% efficiency. How much current does g/ fm e(s:yuay /iwybd4ij;2(it draw 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 120-V ac power soul;g3t)s2fa6*8w(7 rsgditbz u x ojnsu )a7b 5rce. What rms current flows through this dwut 6 ss)n*i) gu7lg352arz;ob 8(xtjaf 7dsbevice?

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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 pea7p2b3yn+ e2ceru 1c jlk current flows throughn2l1 rccj+2 yu37be pe 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 6 4cfexph9hbrw2gx ; 8ac power source. What is the peak voltage across this 8 2g4behp;6 cfxhw 9xrdevice?

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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 copper wire is 0.081 inch. The maximum saf2ax;phvfl/nb i 2ct7ivd+ d-2e 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 thevd fivp2 a/c+-iln 7bth2xd2; electrons? (The number of electron carriers in one cubic centimeter of copper is $8.5 \times 10^{22}$.)

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