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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 s3 9yd jv-)ansinto electricals-sa)ndyj39v energy 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 passukni /(r8+ls3toz q-yes through a wire's full cross section at any poinul y(-oi8/zntk rqs3+t 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+u opc(i hz,b9u:pj3 d 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 ; 3fr2v7 .ozikg 2xg6 f.beuryis the 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 measure of theb4p qj+, d;rzyir

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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 defsxu v5 61hdus)p c7k.fined 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 swd (mljy,liv 8u,z-( 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 depuv/s 0y2wdd-.+doo-rbhc 9teends 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 lmu)h + col.lggnz;6 q2rl ,s.oowest 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. How do the68chuy9fe xk3t uke9- iif ks*w .p32k resistivities of these two wirk 9wxh * tfckui 6-.ys2p3ef i3keu89kes 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 thesqegr)+4yf a4v 7be2. rxvl +u length of the other. How do the resistances of the) 2lsgr vqbyer+u4a4x+ f.ev7se two wires 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-sec*i 5da:4sjva ae.0qshtional area of the other. How do the resistances of thvqsi .:aas*j4h ad5 e0ese 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. Onep v/8 7r h(rehx :v,u6cttdlt6 has twice the length and twice the cross-sectional area of the other. How do the resistances of these two wires compare?6vtu,t vd(hc6:h lr8xtep/ r7

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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 2bzjqz/h l74yfactor does the resistancezb 7ljz/ h2qy4 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 do 3mm9)n5gqv he/a zjg6165j9 fcsjpmkes a 1.0 cm diameter rod have compared to a 2.0 cm diameter rod of the same length and made of t gm19 qh3a65f6 j)jvknpm cejzsmg5/ 9he 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 ,t 4j(hhkqkv +common metals

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19#
 
单选题 ( 1.0 分) 切至整卷模式 搜藏此题  
  Negative temperature coefficx/4*i1o x)5yz 89,w0hggatbps nusr tients 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,rjk):k2iwscli/ b 6k 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 equiva4 ,qb0mopa1bnq8e-h ycd4a7 olent 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 82 p.g)oz2oe cthdsp61a;jkcdoubled, the power dissipated by that circuit wiloo; a g.th18p2kdccp2s)je6z l

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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 resistancn9,m t9 i6hhtke is doubled, the power dissipated by that9 htithkn6m ,9 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, the as5fyj)5w.4 zs1k;q o*jptpm power dissipated by that circuit 1kj; 4jsaty5p*owf5 . zps mq)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 doubled,c9pv kqp2lc70 the power dissipated by that circuit willlc90p c2qkv 7p

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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 perconths.x *mf7x 84z ig2entage is the power on g*8fmsox 7z 24tnixh. 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 respk unzkyln)/3iw2b :t- ect 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 wiresjpz7hd1w l .pv3/sc- x each carrying a current of 3.0 A. One wire has twice the diameter of the other. The ratio of the drift. /l1vjscwzp hp-d 7x3 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 essentially zero 4b4gr 37f msgwat very low temperatures are ref m4w3fr g4gb7serred 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 ix wd6sa05hwmd(qn* o, f 0.67 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 through an o jdllyx3)eeq*m,+h6electroplating apparatus in 2.0 min. What is the average currex6) 3lqhoj+e,m ley *dnt?

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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 1z p9ki 6p0 q9aida+sh)yk0h;j0 s for 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 irmao)rou-: s, f $4.0 \times 10^{16} \; electrons$ 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 13.5o5i1uhm i6ug( A of current, has been left on for 10 min. What is the net number of electrons that have passed through the cof(ho1u u6mi5i gfee 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, i naqney x- 0sdf:,( h3mwyk5r3.)gzszt 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 this much silver? (The silver ions are singly charged, and the ae-3k:z,d5)3rnyhw0m .gqn( a yssf xztomic 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 4.0032hqixaj: 7u).t3uuw3n jbf h A to flow through a resistance of 33u)htu.fa x:j33i h 37qwuj2 nb0 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 resistor if the current thoz(oz n.-nt-9yfr*t g:a f/ ovrough 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 9ogugg3*8ldmq 5 b-rfcurrent 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. What is its resistanln l045siwb/y4rb 4q dal6oxer +b;l0 ce?e b0n4 /0lw6r+54xd 4o yqirbsllb ;al

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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-;c:hk4 py gii2W resistor. How many electrons flow through thycpgk:4 2ii;he 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 of diameter 0.40 inch?z+dm)i 6 -:a.nxrdcqw (The resistivity oca)mx:r+in.6dd z- qwf 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 ann3hkf(7n)z 960mf/xc rq mksd roy3d/d 45 m long, if the resis /kn d k9mr3mx/y(7nsz6oc3qrf0dfh )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 (ra3n)zi-ozu hl (oo()tesistivity $1.68 \times 10^{-8} \; \Omega \cdot m$) 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 (resist -9aj m9cuvw5cobsn+-ivity $1.68 \times 10^{-8} \; \Omega \cdot m$) 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 ohmyesypu63ix je3 vm)v+v2 **xrnvo)f(xj 9:rvs. 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 currenby9 2ic wdj/8spji4j .t through a 10.0-m long 22 gauge (the radius is 0.321 mm) nichrome wire if it is connected to a 12.0-V batteryp.djjjbi4w2/8y ci s 9. (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 cross-section):ne7tzxb ffzao40e n m c*72q, 1.0 cm x 2.0 cm. What is the voltage drop along its length when it carries 40n e) axfc4 z7mot7 :bq0f*zn2e00 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 resistiksil or 9fysx;(7/zd+vity 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 (resistivityzkq9e7 66ipkmdu5zs )*gq c v5 $1.68 \times 10^{-8} \; \Omega \cdot m$) 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 resistfy0 6u qa-bw04pd wdh 6:dk:yjance 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 coeffec*bt6fy.*s bp+jf 4 jicient 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 melting point of indium. The reoy 6a xlw we-ouaw,-f ut5y1+,sistance of the platinum y 6-f ta+-1w5,,eoxlwwou yauwire 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 ljm(c 7e1a9oq g: -vqh$10.0 \; \Omega$ 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 cuj3is *w35sdlwrrent 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 mu b6pgsz7 4yrx:()qmsu ch 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 ligc7h:+ hiiai9w ht bulb designed to be used in a 120c +:ihh ai79wi-V 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 resistan, .ci*g erc:,xvlr -sfce of its heating element?.ci*-lrr:fxgs,v ,c e

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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 8xi f7lwll8h/u 17 spxrated 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 -aela)2colls 54 y b 9zo2:mmwrated 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 3.gmf9b-ra8xprn cnem +i:z6t bw83tit 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 buvv/vgh6j ce4-s- g;ldlb. If 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 x svjn4:ul d.:on 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 costq 7ikn lyc+,xqc fq /mv;j:,r1 to operate a 25-W soldering iron for 8.0 hours, if energy co xcq1:;rl qy qm+,fc 7k/vnji,sts $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 c)a hytdw59 j1*p:/e6fob y op100-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 to a 120-V line for 2.0 hours. m/1q 2t tmww1ph nu89b How much heat energ81wt u/w9hbtqm1p2mn y 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 bata(psak rgx55k5k stq)tyi *2.tery store?(x5gpkt yt5asi)r5*qk2as k.

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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 hougdb* xo:x--e brs?

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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 day. Assum/m* eqah8lg3i ing the power company charges 10 cents for each kilowatt-hour of electricity used, estimaaqmi h*8/3lge te 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 puv e +p;6c:ninlus monitor) is turned on 8.0 hours per day. If electricity costs 10 cents per kWh, how much does it cost to run the computer annu6nn: cpu+i ve;ally?

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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 running a u,ked+kq3 , htn.xp+l,f7sgy 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 y h++,d7k . sk3, xlugqe,tnpfthe 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 z 3 dyl 65o02ist2daoe82u4sry8g u xnheat at the rate of 2.1 kW. The heating element shorts oui4 s6noza8d2u0dy283et lr 5so g2xu yt 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 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 throy4ke 2ea vic;+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 inl;k/2)naw 02ejv ei $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 o9g, si qiff/3wf 2.0 hp has 60% efficiency. How much current dwi9/fsg3q, f ioes 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-Vz(9 /m/qpgoij9yk,r d ac power source. What rms current flows through p9qd /g iym,z/j(9rko 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-Vygn uo4h+d.9iw2 cj z6 ac power source. What peak current flows tzicu94j.d+y6 gnwho2 hrough 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 soulb 6/6r oimy 2z5x5vbkrce. What is the peak voltage across lyo 6rvb6 b2m5zkix /5this 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 mqe.l a,a qt12j;m :fwk--gajc n6hb+jaximum 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 thnj 2 +1kqaht;agb-6lc.fjj , -me:waqe electrons? (The number of electron carriers in one cubic centimeter of copper is $8.5 \times 10^{22}$.)

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