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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 produc , md4/ddpo/ngq yjcakc6 n,(:dv *6fkes electricity by transforming chemical energy into electrical energy6( n,kfj /vopa6dd/:dkc4g* ,ycnq dm 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 cg)zf22kiun. i t;- qqce;p(e tross section at any point per unit on);puf.q2;qt e gi2ckt(ie-zf 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 conventionn02 ds0j ya/ e- glymie(hr9s+ current is taken 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 the same asjfh 8)t; g0g g4r:f8)gbsvkgy

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6#
 
单选题 ( 1.0 分) 切至整卷模式 搜藏此题  
  Car batteries are rateym(hyjkmdvy :c c q.jv:/j5 .;d in "amp-hours." This 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 7v.zkp tv4dwy,4k1nie8 y19oa 5p ecydefined 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 i (w.- lrikyvf;s

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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 *pnz,tbym/b4s p5 ur4 depends 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 re /e, y3t+zc kwf29ecp).f qoqisistivity 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 gf,fn 4g s4qv0twice the length of the other. How do the resistivities of these two wires compareg4nqs fv0 fg4,?

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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 the leng8ylt2f 3wdw ,eth of the other. How do the resistances of these two wires compare, e ld2t8wfy3w?

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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 twice the cross-sectional area of the oth20 u)l76wijpxph; b e)ddza )fer. How do the resistances of these two widbi lx2w0p)p d e 7)fz;6uh)ajres 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 hasp07ao/q 4hg w1vs vj*z twice the length and twice the cross-sectional area of the other. How do the resis/gw*sa0zv7vp1 4 hojq tances 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 i,xt3,z ht:+iuz a7qrz /zihb-s doubled. By what factor does the resista+ i zq/hrhb,t 7i,uzx-:z3ztance 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 compareddf 1y0nck/mz : to a 2.0 cm diameterzd:fc m1n0yk / rod of the same length and made of the 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 mef2e ;q et1+vihi;v6 *dqwp 7sktals

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19#
 
单选题 ( 1.0 分) 切至整卷模式 搜藏此题  
  Negative temperature coefficienmhs(.q0 zjb:byc0z 43dd yi r-ts 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 t csag)y :p1ta1pf nl6kc3+qd:o?

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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 equivalent to)1d3chyc*m b q

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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)t xz1wgov7dy.y7t 4 q, the power dissipated by thv4 go q7wtzxdyy7)1.t at circuit 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 a circuit of constant resistance is doubl w 1wjwjt)a5ay)b9) o +yjmlicy8z 2g)ed, the power dissipated by that wa )8jzgw9ijc bwlo )aymy t1)2) y5j+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 circuit with constant current flowing is doubled, uol kk* ;/s:hcthe power diss*okcs ;u/:hlkipated 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 doujxb ntp*kyqjqt 70 ,1(bled, the powep 17b( x0qytt nqj,*kjr dissipated 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%. qs1uj9 5v-t5dwu6 ori By what percentage is the power on ajoqi-d u t65sv5wu1r9 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 referre2p pey uyy)0w4d 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 wib)hf8qr9 p 88 kb)ia jw7;-mdwxe9 mlwres each 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 e fkw9h rmjp88a l 7b9b -8m;)x)dwqiwwire 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 becomes essx1tvu c0yhyx d 1k27g;entially zero at very low temperatures are referghyv x2;cdk7 u01x1y tred 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 0.67p-m )xh gnff26 C of charge pass 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 thrk+9zayxh8 qb 0;tl8;3wv j*oy;hue lvough an electroplating apparatus in 2.0 min. What is th8l0a 9;*lvt+je;bx ky oz3vhhu ;yq8we average 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 ( odhy6n e(/2fb3fdxs 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 flowing if ;wg/r9 kc bajgppvr2ynn7 33-$4.0 \times 10^{16} \; electrons$ 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, has been left on for 4-c8qwbs gu4z10 min. What is the net number of electrons that have passed through tz448scqub wg- he 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 process, it is desired to depositaq/zdk8( wh kz: u,:gg 40 mg of silver on a metal part by using a current of 2.0 A. How long must the current be allowed to w:/(:g hka8dzk zg ,uqrun to deposit this 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 o:l:fil2)ak (dcp7-uju + zjpto flow through a resistance of 330 W?2kj: -cou+z)jl :f7 uilad(pp

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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 current through it8l e ghfnd1uxu x mo-03p9nb*2 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 will flowy/ jy85ci ql*m?

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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 akg-..m1s pchjl s d8/w yma9/vt 110 V draws 1.40 A of current. What is its resistance?c/18mkwl-ydsh s m .ja.v 9pg/

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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 8j 8*jblbkgwf , 3dnqt e.m90ma 100-W resistor. How many electrons flow through the wire3mw0efbq njlb9 dt.88 *,mgkj 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 of 1.0 m copper wv58t+tl f6m4ae k )ofvire of diameter 0.40 inch? (The resistivity of cofmt4flv)5k 6 o 8ev+atpper 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 hv5xkv t3xb/s tew49bpf0bd; * +ncu7of a circular rod 1.0 cm in diameter and 45 m long, if the resis 9hst+74 3/*5ktpc uwxdxfbevvb0b;n tivity 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 (wtb.98 qfeo- r dv;ny0resistivity $1.68 \times 10^{-8} \; \Omega \cdot m$) 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 (r3wzh0n8 q k wgms.7ee+h;j1ymesistivity $1.68 \times 10^{-8} \; \Omega \cdot m$) 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,j3d*f/q rk;a j 4.0 m long, measures 0.040 ohms. What is its resistivity?

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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 gauge (the radius is 0.321 jr)44pd5-s9 ib8kbmc a97zpf yd fn/pmm) nichrome wire if it is connected to a 12.0-V battery. (The resistivity of nichrome c bnm59b44z/dpyfp)ir- k9fd 7aspj8 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-0xf9wz sm3*drm35 k disection, 1.0 cm x 2.0 cm. What is the voltage drop along its length when * r w09ds3i3 fm5dmzxkit 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 mm and a resistivibfrlx 5a ,:w0 t/uc/sbty 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 (resistivntrupm6+ -mjfg fzr 58gf784 jity $1.68 \times 10^{-8} \; \Omega \cdot m$) 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 resistancm1xw2a 6u-efg m2m 3wqe 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 resistivity of plat.gljzb3pu z fpxr 6zq9,3,ig9inum 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 point ofp3+ds: s jl--- v4 3tszaqyvzb indium. The resistance of the pj a t-zy+lbs-- vqp3s3d: v4szlatinum 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 throe nmh: xge ckh 7.x3r3a;;nu3eugh 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 uts5fl snb.mht, 5(2ir(;d ek*etwk6 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 running on 110 V draws how much cuj,(s mod1u -lcrrent?

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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 ghh9dd9 c1l36s a 6btyfg8dg -a 100-W light bulb designed to be used in a 120-V circ9df h 8lggt963dchysgdb-a 61 uit?

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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 12 +u:ixlp0c gkq+adn2 30 V. What is the resistance of its heating elemenni+duxg0a +32 kcpl: qt?

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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 *gq,k tsmw)h2ozlef)qu46tmn 4s-t: 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 *l.u:a)f yipv 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 does it/jutf0c r3fr/ 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, w xhj 2*omw.zte9*2zd kw f jhig)e)j(,hat 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 V. What is its resistan5 /hf-g eym0+.xk dbvrce?

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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 op* p,pepeimz2 ,erate a 25-W soldering iron for 8.0 hours, if energy coszme,iep pp2, *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 bn5hm4cxbt *1d 7q g5q100-W light 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 tot ko+iz+2h9z5x5 *k gyvm6qw f a 120-V line for 2.0 hours. How much heat energy is qkwo+2z ktfhz6+5i* g9my 5vxproduced?

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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 rwv s xeuzt,2;a* y/(we8f;g genergy does the battery store?eewgtur*xz;, g (w/8; vyaf2s

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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 soldero,.h fvnbqjsso1d.g/fj l. .-b*z2kv ing 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 daoqr6zn ou3l/0y. Assuming the power company charges 10 cents for each kilowatt-hour of electricity used, estimate the annual cost tor/3u6 0o nzlqo 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 hours per day. If 8ffrd::iz1 cq electricity costs 10 cents per kWh, how much does it cost to run th8: zqcfrd1 i:fe 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 c .2 kan c;ikudx*l-1ltost 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 tdaxtk uk l12-;icn*. lhese 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 electric drier o5chve +f( fej-perates on 240 V and generates heat at the rate of 2.1 kW. The heating element shorts out and, in repairing it, the ownefjv5fcee h(+- r shortens 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?

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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 throye00-fl1f aqf ugh $8.0 \; \Omega$ 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 -z dsu/uis/*xcxj6)b xn* 7i-9 d zt kzzzz2)m$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 gk6: 7whn p6fojjrd05 at the rate of 2.0 hp has 60% efficiency. How much currej56n:pk hdg76rf0 owjnt does 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 confe j ,eyx+f/ 4z y.on/hrz87qenected to a 120-V ac power source. What rms current flows r84y.7/fehqyfnz/e +j o,xez through this 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 peak currdp0 4n ooa (43,fshfyuent flows through this devica o,( nfpf0d443uosyhe?

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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 connech7u4c(fjy0ir;o.v) f ikc .y9 dtlw( jted to a 120-V ac power source. What is the peak voltage acr0)kic c;yv.hi7f.(uyfjrol( t4 w9dj oss this device?

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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 maximk3t x-wwpl2uxef 0 btmg+w1):;d:f vfum 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 carriers in one cubic centimeter of cox+;m v0:x1w t) bugw3pk-t l:ffdewf 2pper is $8.5 \times 10^{22}$.)

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