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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://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://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 elu g -rzt;lhx 6t8wtr65x 8gu0lectricity by transforming chemical energy into electrical energ5tz- x8t 6hgg;lu0rtx w6rul8 y 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 ar;rmg(7 q9ik(2ykhre w* si k/ wire's full cross section at any pokrqhk(;9( 7ikymwr/*2s egri int per unit 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 isk2z :bno sjy,wa: u;+f 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 thet;dgozfvm) mt ) y0am(+5/ywk 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." This is a,u, gye 4gwe+ j*fy6ga 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 issd0 3cke6r;5j3t syfj sps 1e0 defined 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 wzd37 e rkqd/r na*9ay4a;cu+kire 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 dep)q+hrlhmwj o,sco m0/7 *2nriends 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 znop6 avam7*a,5g(ehhas the lowest resistivity 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 length of the other. voc)2-q 8jaffHow do the resistivvoc ja ff2)8q-ities of these 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 the length of the otae(g2ii pq; r;her. How do the resistances of these two wi;iig;r eapq2(res 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 twice the cross-sectio 76glhsnkzd .3nal area of the other. How do the resistances of thesehzgl.s k 7nd63 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 length and twice the cross-sh dho::lzn- (ja-al/yectional area of the other. How do :hdoyn(-l-ja /a :h lzthe 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 factobf1w.)+rf cd/0 lb gdpr does the resistance changb/g w1pf +cbd)0df.r le?

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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 ro l2v bkv djjg/:n.)w4ff)8 lhxd have compared to a 2.0 cm diameter rod ogxvv2jdb:/hw )f nkflj 8.)l 4f 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 n /asao 5:gwn+ elub*mlf79 9gcommon 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 of resistivitp6ji2ij,u sd 4m (bzxv80tb9 my

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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?d,yj;3gu kpx 9stjh++

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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 sisk77w 27* me qehka4to

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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 dissipj;u ck,nih0;l5q vz*bated by that cizcjv0q 5*lhu kni,;;brcuit 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 cbkf6/(7 lf ( chk0fguvircuit of constant resistance is doubled, the power dissipatb/u7(cgf h 60fk(kflved 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 circuit with constant cw8t./b l+xi1/i6 adcr h0 cxmhurrent flowing is doubled, the power dissipated by that circuir1h/a m w+6 d.bitx08x chicl/t 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 constanix j29) 4,ijyfiw d1dab/c h v2rlnu2;t resistance is doubled, the power dissipated by tha22d/;b ,a jf)rl4nii j9wc v21u xidyht 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 per91 a jkomndi;p1mb3vhg*b3 (w centag gd1kwmp193vhb jaoi *(;n3bme is the 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 sinusoidg(5x 1tdze 6*ssgj8 idal with respect to time is referred 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 carrying a current of 3.0 A. Onejahrw*0)cm b *sbt3 s w37b vhsjm((w4 wire has twice the diameter of the other. The ratio of the drift velocity ijmwbs(4m hw sb*htjc0 7)wva* br3(3sn 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 resistivity becomes essentially zero ad+tkd5010; vc/*q wae sikkwwt very low temperatures are referred to a dtewvwds1k/qcka5i w0k*+ ;0s

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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 cha h w7 cjklv(r4ftf.ijocnfh ,th51: -6rge 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 through an electroplating apparatus9n s2i dzq9:v6f p4qol in 2.0 min. What is the averpzi6q:9fnql ods 92v4age 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 fomc , h67d sqa.wpss9v wu5v(9xr the current 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 flowing if 7t 31o+)j (hecd qk.if j3gloe$4.0 \times 10^{16} \; electrons$ 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 onjol8fq+;g.ut)e sj-fa u e*5 (wt afs+ for 10 min. What is the net number of electrons that have passed through the co8*.f +j eo+ aeg;l t(ujf)qtau5sw-fsffee 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 deposit 40 mg of silver on a men6 0av a/crm4atal 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 m0 r vanc6a4a/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* jcj6xwuzz /2-h ehru)ku62w.00 A to flow through a resistance of 330 r)2z zw6 2wuh*-ecj /xuuhkj6W?

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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 acp iw- ba.uw8j7ross a 5.0-W resistor if 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 ,-dk i t)07*pgr dcgkf220 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. Whgcjdgzh89,z )eqyu0 kt g5i2 5at is its resistancei)k5ugztg58,q yzg 0hecj2d 9 ?

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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-W resistor. How many electrons fzujvki7r0p/tsr0 :(g0 tvk*f low through the wire i uis:0fj0(7k*g /r 0z vtkpvtrn
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? (The no*)krdf4i0o+q,*,l vrv ;ye*cg-oc br5dz d resistivity 0i ;dyevdro+5),oq zg*clrvb*rdf ,4 ckn-o*of copper 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 circular rod 1.0 cm in diameter and 45 m dm*m+fcquk,4long, if the m4du,k f+qm*cresistivity 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 (resisti 3vkh81jrv-(ioebcjc yx+8 .yvity $1.68 \times 10^{-8} \; \Omega \cdot m$) 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 (resistivqr vs28cwa; :tiyuo +0ity $1.68 \times 10^{-8} \; \Omega \cdot m$) 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.m01 t )izq*qyw0 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 10z q uz ha)4m5-7hhz9vb.0-m long 22 gauge (the radius is 0.321 mm) nichrome wire if it is connect5u)hv- zmb aqzz 4h79hed 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 a3bsqu, .yq)xrectangular cross-section, 1.0 cm x 2.0 cm. What is the voltage drop along itsbx.3yuqsaq ,) 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 mm andkh k6l4ns6 rj; 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 dimyg0 5qyza( :, grwe hg m*943onvq3$1.68 \times 10^{-8} \; \Omega \cdot m$) 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 g)mfn;u3 (/h2(eu e fxox:jge 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 platinuii ks(j*4y5w,pitl5p m 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 of indium k:(m/flf crw:. The resistance of the plmlf:rcf/k:w( atinum 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 throughn 3sy,em lrpu)yr-l,gi2uq/ , 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 cuz3j b.p4t2 gjx-im)sh/l,znugwau ;2rrent 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 runni c ll4d ,xdkx-lngcfr(o5*9s8lxce 34ng 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 resistaqbq az7 ox v4rm3c.r1.nce of a 100-W light bulb designed to be used in a 120-V circuizb vq1xoc 47ar3 q.r.mt?

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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 heatm,zzqkd:ji q-:svs (, ing elemen ,ks(q -m:qdzz, vij:st?

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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 d1+vulgs2-y hbc7 m 9pat $1/4 \; \Omega$. 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 at+m ex -lse)+nl $1/4 \; \Omega$. 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 12u azp .b :py/px2nr-h70 V, what 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, what is its resiqv-0 qacw: /wcstance?

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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 resistancem6a3 y g 8 f-vs8mr0id8xw9, yp*auanz?

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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 opera/uios 2yo:z es5dc0gt lm -/o9te a 25-W soldering iron for 8.0 hours, if energy costs y/iu-/l5do :s m o0o e9tcszg2$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 light bulb use in 8.0 hours?-6m5ata n4zujd 0r9b+wpyj v2

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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 cowx9g lh w2h3k)be e,r)nnected to a 120-V line for 2.0 hours. How much heat energy is producedewl, gh9 he3 ))k2brwx?

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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 i tkj 5vnb c6p)e*wq*012 V and 160 A-h. How much energy does the battery store?vwk 5*qj)0i 6cnbep*t

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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 solderipj emxfli5v1-,)+gx w ng 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 yt7hug k y8j/+on 10 hours per day. Assuming the power company charges 10 cents for each kilowatt-hour of electricity used, k8y +yhj/ut7g estimate the annual 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 monitor) is turnev+h+ t6;tkjl2zf 8redd on 8.0 hours per day. If electricity costs 10 cents per k rh+6jde8;+ l2 fztkvtWh, 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 8q/ -7 vi q54*iphmx4luuo clcthe 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 b mc p*7/liul44q8uiqo h-v5cxulbs for 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 electric drier operates on 240 V and generates hea5f2xvshb lfs08+ n8a g2lq.bot 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. Io805lffvl2sqba+n2h 8sb g .xn 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 thr - d -dief,ideow/*af6ough $8.0 \; \Omega$ 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 wb,z+s71.1dezsjxbxr* j/ml $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 nxdzp 86 f7jbsha:fq n;k5f(02.0 hp has 60% efficiency. How much current does it draw from a 120-Vf fds x6(a8:; kj0qpn7fh5nzb 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 source. What rms eh lel4-/ft o9vwyl/a *2ds6w pu;da, ux1 fu(current flows through this devic/uew9y64tvu 1h 2fls;pu(l eol wf/add, a-x* e?

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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 pergs wry /e.-f7/d(t wower source. What peak current flows through this t7/( y-rsg.wfdwe/redevice?

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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 pj:pob etq(n8h d 5eb*5x:en8kower source. What is the peak voltage across thk:8dj8h 5ee 5x qpn*: (tnbobeis 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 ,ptcj3ufer zc9u7 +vdbls+qbg2z+,, 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 elejb +ubsg u+ql 9f3,dz+t,zc ,2rc7v epctron carriers in one cubic centimeter of copper is $8.5 \times 10^{22}$.)

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