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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://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

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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 ;fwx6k c,:x)4u.ffn tjds3 yg into electrical energy du4 ;: 6,g y.fxf)jtwkcsxn f3is 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 chu67 :k4hevjbl* 7iv2 y3 gzprbarge that passes through a wire's full cross section at any point per unit of time b*k p u2by:jgl 76zv37 irh4veis 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 th3l e*,ilnggjqwh- : tm+o(4v be 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 v h 8)c0vztc6ec10vcpas

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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 rugnc 7g u-:*w8kt;yb"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 defined v3c: i,(j bkhr-j7vhfas

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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 wireq- aazzi,dhvtih 5ys894 a r99 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 tip; 7 l ,ds3ifawl.y/wire 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 lotprqzv ( j85a9west 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 wgpas)l.12o rthe length of the other. How do the resistivities of these two wires cow.1gl )2ar opsmpare?

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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 bvqb2;w xo 4rnk, ,/kyhas twice the length of the other. How do the resistances of these two wi2,q wxb4 /,k brkvnoy;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-sectionali/kw ps7 b0 1p)uf;eteks2:ji area of the other. 7pk)k/wtu p1bjseie f:2; 0 is How do the resistances 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 wiresi)snk mf,w16 142xwla/ r waxp. One has twice the length and twice the cross-sectional area of the other. How do the resistances of these two / 2wxaxsirp 41w 1 m)lwank6f,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 wirelqg qd 75-8kgjtt,io 4 is doubled and the radius is doubled. By what factor does t7 tjqdg 4igq-k5 ,o8lthe resistance 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 compared todaqz y c0)(.fm a 2.0 cm diameter rod of the same length and made of the sameqd ma.)c0fzy( 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 metaled+js d7lts/v7 at36clpd *(ws

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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 resik*0ltx a;gxvlgk.;9u stivity

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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 toj80xrmupp s24 i8y6;gww-lzje jr(1o?

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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 equiva+9bglkf1:ov qx b q4y6lent 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 doublka9sw(0e zg.5h:qjn 5buua2 hed, the power dissipated by that ci e :g9ua hb.0 a55w(sjqznku2hrcuit 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 ;/9o:odpovu6 fwjfn2 is doubled, the power dissipovudo jp29f/: o6f;wnated 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 cuk u-mv94i6xyscoq p.)rrent flowing is doubled, the power dissipated by that cu4 qk.) icyx9m v6-opsircuit 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 s3 mxyvbkh9hc2,a 6j,circuit of constant resistance is doubled, the power dissipat h3k,h9b,mc2ajsyvx 6ed 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 percew0 gcw+ 5. qy c.9syxr47zqj6gkawt0zntage is the powerck+t6a5yzcj.gg.4 q 0w rqx0 s9w zyw7 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 tn , n5v)rthn.wo 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. dx27w+p2x qpo One wire has twice the diameter of the other. The ratio of the drift velocity in the smaller diameter wire to that in thpx+7oqw2 dpx 2e 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 -r8 f:mas:4 hjk4vbtiessentially zero at very low temperatures are referrej4kbas8 -h 4miv:t:r fd 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 pas sv:6iko6wpd7s 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. What ij.wktzjgu gmc0 4;g/o,5b :5 eeep ix0s the aup io0gbg gjj.et5e/5m:wkx, z0e ;c 4verage 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 for2nnu 8ct lj*2r1r;ndx 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 i3 ge/did i ikg4qs)3($4.0 \times 10^{16} \; electrons$ 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 1e.xu +b.n bj2t3.5 A of current, has been left on for 10 min. What in. b2xj+u .bets the net number of electrons that have 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 process, it ifu7i evk,07 j+ v))dbb c)aqfibi7 r(zs desired to deposit 40 mg of silver on a metal part by 7vq,b)0 i(7vbd zc)f r+ aiufb eik)j7using 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.)

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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 reqb v4bgb00,,mxklh2roe (mx2z0 jr y8fuired to cause 4.00 A to flow through a resistance j2m2b rb40,(o0kv8,yh mg z bref0 lxxof 330 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 5b)lh )j x-juwu2 fb.i:1hcb.i.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 220 V. What current will ms :jw-lx75vwty:i 0 ,xj + pofekt6a,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 1.2,c be4h;uagb40 A of current. What is its resistance?;uba4c h2bg e,

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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 flo fxua8o4r)j7ebm 8 i5tw through theu i485ob7e jmaf8txr) 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 of 1.0 m copper wire ofgci 2wrigt1-5i +hg d 4d)msg1 diameter 0.40 inch? (The resistivity of copper is miig gw5)rg- + 124s1hgi dtdc$1.68 \times 10^{-8} \; \Omega \cdot m$.)

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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- gqaw71/o2,s smhcu jm zz3a2 45 m long, if the resi2 c /zmosgm3q2h1sw,- j7auza stivity 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 (resistivtcmzf;q:sx2. ity $1.68 \times 10^{-8} \; \Omega \cdot m$) 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 wihg4o-lnsv x 4c8fvdz.oh 9:e: re (resistivity $1.68 \times 10^{-8} \; \Omega \cdot m$) 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 lgj 5) ucf-ax)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 mmp47 q50f k:lvfkz5f5l u y+y(the radius is 0.321 mm) nichrome wire if it is connected toqzku04 p:f f557vklyy5+m fm l 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 coq)mdqt11u 3k7l *i at ay*n.lc j8;x t0g7hyom long and of rectangular cross-section, 1.0 cm x 2.0 cm. What is the voltage drop along its length when it carries 4000 A? (The resistivity of copper is 0l1yaa 8)xk 1t 3itgd*ht7nq*7uo o.y;jcmql$1.68 \times 10^{-8} \Omega \cdot m$)

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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 ohjp-s y;9nfxo;p8j9 qdn6 x4j f 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 coppjsp 6*am +j0 -jp3v05sp8nh5wnu cld.(rz muker 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 resiqe nff*213ydu/7yphq77n c pcstance 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 oq80gkh psy94a f 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 melting point of /:ppsfv2p 8u z ezmp(2ql1*reindium. The resistancsppvl1p* z/ qf r 82peem2(:zue of the 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 through an jc /sxgao,pbn 846o9k $10.0 \; \Omega$ 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 15kk8 z1 u cfqd0r7b,xhr68kem 200 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 running on 110 V draws how much currv(4:t7l zplyjcjod: 5ent?

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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 bulb designed to be u vhx )c-sc e4:)c0(l0oaukp;qfv;p hg sed in a 120-V circuit?f kgc:v; c)lpc- ue;oxh)s0 q0pv4a(h

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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 htp 5gr./jrz,)t(yib0 V. What is the resistance of its heating elementrh . ,by5tr(tig p/jz)?

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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 a (4v/ko3 uhiunw5d /nbt $1/4 \; \Omega$. 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 ra)zgp5xrm: y:z ted 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 draw?-s *7 bg(6-i+ hl4yezpheit mik1mw;t

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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. 4oin1i4 ,a5dux5j gz oIf it is used at 120 V, 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 ox jlb1dyzza ays2 l90 .8t*j/zn 110 V. 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 iron for 8.0 h 1x4us qqg av+1 sae.)f0aio.g ;2vxmzours, if energy coz02a xg+1 xo. vumsq 14;) aisfgave.qsts $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 bu3kix;d0az dw :lb 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 connecerud h6)6q 2gde9k*eb9: nossted to a 120-V line for 2.0 hours. How much heat energy is produced? q96kb: )s rsegd 6*92eehnduo

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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 ak8zwgy,zy2pj suat6 64rr1+dnd 160 A-h. How much energy does the battery store? ,d2kyp64zj1yuar+ zw 6 8strg

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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 soldering iron use in 8.0 hourmdc +2oorch 95;ue(xms?

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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 pe w- a:;nhre :yy1 cijs0,nda+mr day. Assuming the power company charges 10 cents for each kilowatt-hour of electricity used, estimate the annual cost to operate the b0 rhainym:njy-ea;cw:ds+,1ulb.

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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 rvw f1phv(3k 9-tthl1 hours per day. If electricity costs 10 cents per kWh, how much does khf vt tv (1rh13l-9pwit 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 r.lwvo5oo )28hfsim j +c1kim,unning 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 electricity costs 8.0 cents perc)8, o +5m1wkfohoii.s2v lmj 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 l . +i* 1lmwjh/,szuhlk5l.v e240 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 reality, the resistivity of the wire will depend on its temperature.) What effect will the repair have on the power di,+hlmk5z /1 *lvwejs.uillh. ssipated 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 thdw*lcu.a/4 5cl zyty);py 3z vrough $8.0 \; \Omega$ 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 cost aa2 ye8 9-*dqs)fxrprs $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%egc43k dlef s*j:zx2+ efficiency. How much currentle4j: k*ec2 3 sgzf+xd 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 connected to a 120-Ve,bqj m wx 6bxdmg+2to2;9 5n7my.n jo ac power source. What rms current flows through th522 qno,. go;mjy9ndjm6 b ex7twbx+ mis 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 8z2(w .t 96ggla+z7lsxkkzempeak current flows through thz 6mxga9ezt+7k2 .lgswl8z(kis 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 5xf9+egs 3tkmid3 dg5is the peak voltage across this devic+5 m3fikdg5x9te 3gsde?

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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 safe current it 785kcxvoflki5 :skj3 n dj :+ccan carry (in order to prevent fire danger in buildikc35f8 vx5 ilc7js+ ::knokjdng 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 $8.5 \times 10^{22}$.)

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