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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 electricity by transforming chemical energy into el ,l)g ;hj p*x/j;ysltjectrical energy i/;jyjlx*s ;thjgl ), ps 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 :sg er *li4m(oyie+ twh;, um(a wire's full cross section at any point per unit of time is referred ;e e wy4,*mt: uilsm(goh(ir+ 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 direr;s tx8rm,oa v0 2vp.lction 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 k cdqp3/:l8/wje(ulq 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 of thel1w t/5oznqu;jc5 vq*(hsje 2h, bnr. ir

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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 defin4 i 9azm* w:-lkt5bk1 ypg 1wv+(xdadyed 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 dzf9-emt)/k ;d4b jca d7ku8pwire 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 depends qr(* 3dfja2l yi5:sp+np fq 0qon

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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 resistivity vw1 e*x*4dy 5n.qogexu alue?

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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 of6 qsmy:bfua ce+ p.77h the other. How do the resie7 + bms auq7yp:ch6.fstivities 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 thj7ywa3w6 ap jc8a; uq:e length of the other. How do the resistances of these two wiresa8qcyj wwaja;3pu 6 7: 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-sectzs:moud9 0 dnza;tlc*z6i 25xional area of the other. How do the resistances of these two w9actzx 6sudzdoi 2;:*m 5 ln0zires 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 wisag)3, w pjar5z,9 fsyres. One has twice the length and twice the cross-sectional area of the other. How do the resistances of5,, grwa)s y9p 3szafj 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 factor does45 hb1:9dsvx eqj r/ng the res j:dv/b5 49 gnqrexsh1istance 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(1j8 u+gugnth compared to a 2.0 cm diameter rod of the same length u(+h jug1gn t8and 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 metal pxf 72eb2baw:s

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19#
 
单选题 ( 1.0 分) 切至整卷模式 搜藏此题  
  Negative temperature coeffyi0a09b f1vaozd 3q:p icients 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 equivalentu1xm 1 b/t2lnwi9fj p.. xdz7c to?

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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 eq3rpt dnxi3z4ifi s ql) v;27w9z o-dq7uivalent 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 diss:-ipn nzjmf/v9b ,ss6ipated fjnb6svspzn :i9,-m /by that 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 resistsb6liz,y7,qc p/:.1ij thh b ,ekdjw-ance is doubled, the power disslb t,/w q,jei7b chh, yz.1 d:6sijkp-ipated 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 cir:xku8 w rs-9azcuit with constant current flowing is doubled, the power dissipated by that cu:s8ak zxr- 9wircuit 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 mtqpcpy g;-:5)n5f qn/ c4 fgjcircuit of constant resistance is doubled, the power dis;:t55cg/ m- n4ypqg fcpjf)nqsipated 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(jd 52x6u1 bjie k(detslsa)0 5.0%. By what percentage is the powe0 x6sed b)t 2k(isladju15j(er 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 +s.nze mnes3m c( j)g4respect 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 carryingrzy bpwg0*/r(p6 r 6 v+rfdvw/ a current of 3.0 A. One wire has twice the diameter of the other. The ratio of the dvz6rr6 d+r(f/0 r*/wp gpy vwbrift 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 resistivity becomes essentis :mmcbz(tg0, ally zero at very low temperatures ars bc:mt ,m0z(ge referred 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 pass a point i:vmcc*fr -rt.n 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 thrbi v 98z :bmzhb99)-zz+xrflrough an electroplating apparatus in 2.0 min. What is the avzvr h fmz9z+l): bx89bri-b 9zerage 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. g9+peo .u/kt ubgnbw(q;:6zwil0v 9 v50 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 g s)02ysx/ xyj$4.0 \times 10^{16} \; electrons$ 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 . a7ov0 hioo-p7m6xr ,ladi2 g10 min. Whatrlgx-i 7v7mo idh620pa oo. a, is 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 is desirxah 7 imj*z3p1ed 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 108.1j* ai pmh3z7x)

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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 actzu))nmmxs8i x al42z;63hq resistance of sq8h );uzizmatx6l xm 3 )n24c330 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 resi/ ,rglzh.b b dd,t3*6rci: xc 7bfqn0lstor 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 connectilrym;q lt898t, di ary.y.(hed 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 curr wrh2znpm9. xvx;6 /ldent. What is its resistanceznwlrp/ 2.9v x6m;dxh?

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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 connectedc+ z59es , kcllqh(mj. to a 100-W resistor. How many electrons flow through t h l( kecc+msj9,.5zqlhe 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 wi1; si l3 w9zf 3l:ol8huahnwx)re of diameter 0.40 inch? (The resistivity wh8 nzull;3hxalf 3i91os: )wof 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 lohkzs(/ d kt)4gng, if the resistivity i(d/t )kzsgkh 4s $1.4 \times 10^{-8} \; \Omega \cdot m$?

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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 (resi(f wgmv0,ws6s;ct jq5stivity $1.68 \times 10^{-8} \; \Omega \cdot m$) 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 (r *: 6vsd 1ozp,jmw10scouuz*tesistivity $1.68 \times 10^{-8} \; \Omega \cdot m$) 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.p*ql7isj emsw f(+7o8a lb4/k 3l8toc 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 gaugev:bxaa(q*c *ww u*bp1 (the radius is 0.321 mm) nichrome wire if it is connected to q1b*** cabupxw: wa(v 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 ogop,ea-3)o3 whayih:f rectangular cross-section, 1.0 cm x 2.0 cm. What is th,o-hwa g3h:i a3oype)e voltage drop 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 mm and a reco6 (hjg: xrtx6 qj,:(;htw gvsistivity 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 wir kw7vuk15co* b;cg /3az mjk3ce (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 res qbeex;sx/reu:j02 7histance 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 iwq1 ip6y5re-q-,jql6 gr 1yoof 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 melt(q+.o(nmb7 m67qua, 4k 3qgqacadytking point of indium. The resistance of the platin c+yaqaqq7 3am q7tg b(n6k mo.ku(d4,um 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 thg7h68bim7jgu ov+ 8 cnrough 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 wi.ncgw4fon + ,hll 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 curre 1ya whb w-luno44 .jh;qlg+(s q/qd,dnt?

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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 100gfj218,:x v)ih) 1jaz mbd n k;agh9io-W light bulb designed to be used in a 120-Vkgdao)mh:j h;in ,agj1fbz29i81 xv) circuit?

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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 renl(bb 5.tduv 6sistance of its heating element?tv(ulb5d .b6n

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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 a;gy/ 6qjerb3rated 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 v;t ytj v;tjgov*mk/pk xn*j6 h2b8,(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 cx *tr9f 12hjqc.ikug 8 vpjj+d2+sk 4uurrent 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 ./cz x*rv:i ev120 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 on 110 V. - df3vr(uzt3 : mm4,mcvz9 xzwWhat 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 hours, if e5pg9 ydhb g8uqpnoq) :(n0s9 jnergy cog(ybgn59pjd nq:u) p sq8 09hosts $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?ls xq i )(jew1p8gury8gc356 a

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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 muchb x9+9) rq:q / 4tstqje pfwx5)a,njiu heat energy q9ef+rjj5 w xsq)x)pt/,4tnb9:i uaq 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 12 V and 160 A-h. How much energy does the batterjvquvo0st7yvfjo::1uahj h+ 83 x5o) 9; g qhxy store?joxj93vv xtjof:5ya:g0+uh7q ;o hqvu8) hs1

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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 solder 2p8h3*cexb( tl hile-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 per11ygo,2fnmzeqv pk ,, day. Assuming the power company charges 10 cents for each kilowk, gf 1y2,nzpome1 ,qvatt-hour of electricity used, 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 (comsvn/; mbocm*4yfwz (*5xu8xu* dazu.r1v 4 s oputer plus monitor) is turned on 8.0 hours per day. If electricity costs 1crobmnu5*y4u zoa( sxvz /x1**v8s; udw4.fm 0 cents 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 bill included(auexx) o+:yl r,n7ii 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 electricity cos ,uliy7oix(e r:nxa)+ts 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 generasmw )ih3z p z84z7jh1etes heat at the rate of 2.1 kW. The heating element shorts out and, in repairing it, the owner shortens the Nic13)p shwmzjhi7 zz4e8hrome 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 thr yule*lwb:c * e2u(nh/ough $8.0 \; \Omega$ 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/u x;mie*3fgljj (uh +s $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 smb*tec+54b.c -zsxkf4rl8 r;s exb3 the rate of 2.0 hp has 60% efficiency. How much current does it draw ffbxc;s8rb.semb*t kz c44s5+ex 3 lr -rom 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 connecggzv)rg8de:7o5 ft a t hy )zg(*wb99uted to a 120-V ac power source. What rms current flows throug(vggtgtz:)bwg zf799uhr8y*d5 a eo) h 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 currenje5t4wgjh4(j fnbk -l0s4yx4 t flows through5g jy4sjwlj(-4bh4nk t0 fx4e 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*j;r,s lec y bzfy4)b9. What is the peak voltage across t4, yje *)zcrblsf9b;yhis 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.(ve1v3b k-tu1 veql5j:bwgjjun ; -)a 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 carriers in one cubic centim) u wk l-5vjgejave:b u1v bq;1(n-jt3eter of copper is $8.5 \times 10^{22}$.)

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