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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 electrx2 2hznd:poufkg/k;5ical energy is calle:;f okuh2 xd /znk2gp5d 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 fulfmvi,+laux 07 t. g*4zvhg/dc l cross section at any point per unit of f ,*vm +4g70audg hlztcixv. /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 is taken to be the directipa mk6pwb548ot yy5-y on 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 as0jjaxwv0 hg m9ok-3,q(e b*vv

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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 measu2oeu8d xa:km q;jljb, y-0e ,dre 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 augmsboyft8+slg 50 ,6 s

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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 bw5u:y ;ojg+ggd 20wfyyd: -uis

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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 dep4 i q+w8e-zehqends 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 resistivity valu6 m*56b7nyxlbce*up-ig5 i y x+nh h6ie?

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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.,t vlfjw +e+rv6 b1-sc1rbw13( r z/ewr2b fve One has twice the length of the other. How do the resistivities of these two fb ev 3v/r rw 1rlz2sr+w1e vbe+c1ft6bjw(,-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 other. How dbs hrzz) 5y .gqq/jh-.o the resistances of the ).g- z .sh5hyjqqbr/zse 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 crossnh:cdi6o -)r;aczpzt la ,8w :-sectional area of the other. How do the resistances :zh)no;cl:a dz,cpw 86 itr-aof 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 wires. One has twice t j9yea 9d/wi()sn il6khe length and twice the cross-sectional area of the other. How do the resistancesi)/9i syd6 wnl ae9k(j 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 i5:pm*8 3llwus dyey88 i,o whm( cht5ws doubled and the radius is doubled. By what factor does the resistance chan lw8eih*hls3u :ym 8wwt5p c5d(, yom8ge?

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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 to a 2.0 crx3v0y,b/yicm diameter rod of the same length and madexyr,i03y /cbv 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 h+ 37 dy5b.nuvg6;ubwipt -y(ehz qw7metals

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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 resist lyf3 6o d(c18szd5ex/ qyhiw2ivity

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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?mjm3tdy,5 y9v

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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 tm s* via:e 5/u l8zo:oat48hf6reec- 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 po 9lvs7rn+j2 ji )ksgr*wer dissipated by that circuit wis+*vnsg lj29 ij) rk7rll

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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 doubled, the power5k: m,pbsjdxg7: h67/ldzkg k dissipated by that j:7: bkdz hlg7pkxksd5 g/m,6circuit 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 plyazg6 0-d1wr-jsw6 v wn:.on4txv.pg /*iyv ower diptw16 / jvg-nd 0o4zlyisgyvr: wwn. *-a 6vx.ssipated 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 resiswm i/6fd*z4p)e-wlbitance is doubled, the power dissipated by that c 4fdzlie-* mw/i6pb)w ircuit 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 percentaac xt ;e.g*94v,wdwib ge i,gxiw*4a ;9 btw decv.s 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 sinusoidal with respect to time is7rubkobae+w /a4aw)y ,n / ol+ 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. One wire wmeylw;( a8twyp 4-d*has twice the diamwe plw(48 yw; -ad*ytmeter of the other. The ratio of the drift 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 jcc3qm(q6q- tbecomes essentially zero at very low temperatures are re(cq cjq6q -m3tferred 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 poin(62 p 28jf ci8 /b4zpvnt7aiur fwb/oit 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 electx6i *6 rlgo )gtnjena3ws:: 1oroplating apparatus in 2.0 min. What is t6*ex :nsog6ia )wr3nol:j1tg he 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 pasyjq l e403+jeohw ;s2as by a point in 10 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* w2,)zt c.90paain yiwld,qg if $4.0 \times 10^{16} \; electrons$ 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 leftj x8qxja .q-mek/tq1 l5d8)xoz/z1l fhdu9x. on for 10 min. What is the net number of electrons that have passed through the cof9 qqdhzj1qf5xxzo-ud8/jkatl8x.mx .e l 1/)fee 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 4jw y.38m2f uy gyzl/i8e5ky)h0 mg of silver on a metal part by usy.83kgwi /zm yel8 j)5hyy f2uing 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 required to cause 4.00 e4 ug64ha mrc5oq,f ;zq8+vkm A to flow through a resistance vhg 5 6 8,em f4uz;mqqk+raoc4of 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 5.0-W resistor if the current througw hi,13llr c6eh 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 flowbbe 2q8v5n /en?

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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 curren4rv;/+ n odvdzt. What is its resistance?n zd4drov ;v+/

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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 co-wtv a;i,it)ehy *5 srnnected to a 100-W resistor. How many electrons flow through tve,i ;*5-styhari)wt 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 di) + (cbqig1v gmtu:o1eameter 0.40 inch? (The resistivity of co1u+ gv:)iet g cob1(mqpper 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 sx-vhlcva aw)15mk ;+ circular rod 1.0 cm in diameter and 45 m long, if the resistivity ismh c -x1lsvw+vaa;k) 5 $1.4 \times 10^{-8} \; \Omega \cdot m$?

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45#
 
单选题 ( 1.0 分) 切至整卷模式 搜藏此题  
  What length of copperod jr2-*u- pwn ie,es: wire (resistivity $1.68 \times 10^{-8} \; \Omega \cdot m$) 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 (resnlg p 6uy8.vozk pl hdy),c:um+ 0:p-pistivity $1.68 \times 10^{-8} \; \Omega \cdot m$) 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 q 3 6qlp5y;t*uir- mgtm 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-e;f47yj gk, m;rz eoo-m long 22 gauge (the radius is 0.321 mm) nichrome wire if it ;-kyezr oemo gj7, ;f4is connected 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 ofr 8uwzm(wk( s+ 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 copper8 +(wsrmwkz (u 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 nichrom qw( 6/ns+4iramtcq:ijix4 )me wire has a radius of 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 copper wire (resistivity 3ax abuuz(lzj,-ef ., $1.68 \times 10^{-8} \; \Omega \cdot m$) 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 resi9cm1 gm3tek4o2j ut d/stance 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 3ga)iyntj*a/ 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 dixgqojwbn0 rj;p -32x m9hj, 7etermine the melting point of indium. The resistance of the platinum w0o jnxj ;w7p29x3mhjqrgi , b-ire 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 u yuivbk*k-:*$10.0 \; \Omega$ 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 cur2 ogvf-gctyl t9;m*+axnd * wgkj(/( arent 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 dra 2 i6gf 7to4d0l4-o7qr/qjrloxh r a3ews 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 resistance of a 100-W light bulb des 7,vgup1 pgrz5igned to be used in a 120-V 1vp p,u5r7zgg 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 g ke;dd 7.7azsat 120 V. What is the resistance of its heating element?sd.7eg; kaz d7

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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 ra78ods)i(t gwri ce+ l.ted 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 e;n(; c;dy oxpnk/pr 8*dsm)krated 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 bssrk d9k3ejp3 7k8oa3s+ q.3nxebf.-wkz u0it 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, whahajw)tdci7g 8gklm;8,vs7se/ s) f .v t 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 iddo wv 5m*h4.pzocma46l t n,:ca*r (rs 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 25sa-ta;q e 6 +p8awdukvjb9c3 2-W soldering iron for 8.0 hours, if energy costs ujat3 b9qwd 8sp2va+ace6-;k $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.n:yj-5q f/ tir0 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. How much hu.bfrvr eqggmrn4693 -h;4qseat energy is pru e fr rg3h;.4bs4qgmvnrq96-oduced?

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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 muchoi :/ /vdtx/p qty)w:w energy does the battery store? pwtq:o/t /) ivx/w:dy

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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 +uuite(v0) fl a 25-W soldering 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 day. Assuming the power compu kj-znsl *by n*vx,-sm*k/i+ any charges 10 cents for each kilowatt-hour of electr sskb*knj**+n v-,mzu/xil-y icity 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 (computer plus monitor) ix+t m)eea2 4bas turned on 8.0 hours per day. If electricity costs 10 cents per kWh, how much does i)te42b mexa+a t 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 oo1s7ci*gk 1 g2c9vea i2v9v dbill included 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 monthl2c iag2ecv17osog*91vdvi k9 y 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 j e-a hj3aed4 rzt1ekazigoz7 / ja rq0o654.4240 V and generates heat at te a7jg to6z e40karroz1.dhijejq54z43 aa /-he 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 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 through rx. 0g29in5pebye7v m $8.0 \; \Omega$ 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*1 m/a0w skuhys $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% efficiency. How much c0mz7o+j fyr(j4h e6+yxgii m;urrent does it draw from a 120-V li+mj(f eirm0z4i+yygho 7x; 6jne? ($1 \; hp = 746 \; W$)

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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. Wi+ 2y( ,4/3jyh;b p0cnjdb9kdwzljkxhat rms current flows through this dev(zj c d34bjx h/ildjb0;,npw+kk2 yy 9ice?

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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 conneijr4p1ihpld o 4d b./(z8r ypf5e8 -dacted to a 120-V ac power source. What peak current flows through th/5d1db di4oi.-eyz4j 8 ppah(fp 8lrris 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 i +bw3yvne9 gj:s the peak voltage acroe:gb+9 3nvjw yss 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 maximum safe current it ca 8ygo oh0:.5goj0g mtfn 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 electrong0oty5j mgo 0g8h:fo . carriers in one cubic centimeter of copper is $8.5 \times 10^{22}$.)

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