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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 ene9 ucqv)yt / n39q0ksfjrgy into electrical tyf qu/ c) 0ks93nqj9venergy 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 a wire's 8 36fj3w m ayema.wn, p)hdfr*full cross section at any point per unit of time is referred to a a6r e)fj h.,*fwnpymdw3m83 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 di/*st9ut9fo2ph, uui yrection 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 samerxrq5 ieqg04*3 mbuo 3 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 "ams8rkjk4)ant 6xc7) f) *lsfhyp-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 definedbhea4s 9,8j af 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 d pu1zfjm/h-.r5q( 0 l4vw yntwire 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 dependsv:t dwly at0pd td(6*( 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 tm20 m7 lwfwj b1r8hw1d bhz4m4he 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. Honl:vubt.-o/k6alrj c-v d .r:w do the resistivities of thl-v -auckr/v jnl 6::do t.rb.ese 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. On e+ms50ye7q 3 hztw) 5ewhf1ffe has twice the length of the other. How do the resistances of these two wir3 eemh05hfs zt+ff751q ewy) wes 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-sectional area of the other.*mcgl iav*u,-s c (9ut How do the ,l9sui -*acg*mu (vc tresistances 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 wires. One has twice the length and twice the cro)zvl 8l tcl(*,n1jcglss-sectional area of the other. How do the resistances c z(vc* 8)lljgll1nt,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 factor d9vskx jh :ahvib/;+/x oes t svi;: vh/x9k+h x/bjahe 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 u.td5curik a t+nex 6q f u)8u5-s/hd7cm diameter rod have compared to a 2.0 cm diamet/7dr uu ttua6hc5si5k8x -.qd uf) n+eer rod of 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 common meta+zv3h +v, 9mmv)d j1cqw k0i; cyol8uvila /u.ls

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19#
 
单选题 ( 1.0 分) 切至整卷模式 搜藏此题  
  Negative temperature coefficis,hmh 4b op p9/iwu1g6ents 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 hytzxf ;u9j4zup9q7 0/ akl4ato?

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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 equivalentrvrporeb9k*+ b* 5nb,9aryk4 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 dou0cb l(xc nm7;0dxbq,e1e+ p eke+bqd1bled, the power dissipated by that circuitb 1e c;q,ec+x7pqn0bxle0 dk e( 1b+md 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 resis6z;xjfx((es k tance is doubled, the power disx(kj(fe6xz; s sipated 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 current flowing is double gz11z(k2s5n* udmb myd, the power dissipated by that ysd n 5*z21mg(bzu1 mkcircuit 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 aby/b)8u/:zz 2,6vn dpo1njz0 h fpsf i circuit of constant resistance is doubled, the powerzjs8f2 zv ipny:hn)/,bz1upfd / 60bo dissipated 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 vol6te:w j psm46gtage output is reduced by 5.0%. By what percentage is m tgj6sw4ep 6: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 is refj)mf.c31r)fs z gx,yverred 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 Azat08rj( r,ys9 h 7v ovdeg,3x. One wire has twice the diameter of the other. The ratio of the drift veloox ,rvg y9rj sv (h3teda7z0,8city 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 at very lk38l4 in c(gwyow temperatures n8k (i lc43ywgare 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 inszo6/ppy,pz3, . fkraj ip30yv z 99ks 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 pashxal8(t ac9q ,ses through an electroplating apparatus in 2.0 min. What is the average current?qa, ht 9c8l(xa

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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 f gzwws n9l9:a(0y pzo +hbe:x1or 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 flowinb2aac mh2o*dfh 4b(a0g 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 cursp)fw0yckfsq b) w4 8kilp57)rent, has been left on for 10 min. What is the net 7k4p8lw))fc) bwsfyp q5i k0snumber 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 pk 5h:-1jn(isok) s dunrocess, it 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 t5 :khsos1 ujknn ()di-he 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 r3nsk +wtmg,74iyk/ w cequired to cause 4.00 A to flow through a resistanc4 ti+3nk c,my7kg sw/we of 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 throughx/u .u)g5jsml 1y8a:lvc 5v sg 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 ciz3;wsw;1js+r(vv(yjm ifx - onnected 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 1.49/ebmmm( 7gec 0 A of current. What is its resistance7mc9b(m/me eg ?

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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 connected6 yg8;txer0oz to a 100-W resistor. How many electrons flow through th o y0t6rx;zeg8e 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 0.4 txv2,jin+ tw90 inch? (The resistivity of cvw9 2xt+,j intopper 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 d. 9rwwze,wv u,yjo 7t5iameter and 45 m long, if thj,5 y9vw7wwuor,t.ze e resistivity 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 (b-((vfg2.njv ; p pznuresistivity $1.68 \times 10^{-8} \; \Omega \cdot m$) 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 (5 a:qi9mwtvh2 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 0.040x -tb m:ju7x *yrkvr/)3gidk + 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 10.0zmckgr9(fy o-ufy: ),2ye (tt-m long 22 gauge (the radius is 0.321 mm) nichrome wire if it is connecte tz2y9fkreft:my ,-(c g)uo y(d 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 rectangular crb//sudxylzy 9exma (5-h wk7+oss-section, 1.0 cm x 2.0 cm. What is the voltage drop along its length when it carrzy//( xw yhl7-k5s x ube+9admies 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 rc5h yi+-ed pmvh2(gfx .cgln+c)n: z2 esistivity 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 (r) ur lu;c6n7xuesistivity $1.68 \times 10^{-8} \; \Omega \cdot m$) 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 ofdo*l/uw ;l ;b7fmrk7 zh hb(:i $18 \Omega$ 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 resistivitj4;uzs1 0djx vy 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 usr;bh(lnd ( tfogg (:*qed to determine the melting point of indium. The resistance of the platinur((*t qhdf ;nlg:og(b m 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 throuppcuyq d4odd,b3x 5t5:3p1ia8kn)3/thdlq ogh 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 will it dse crc(q)- ms1raw?

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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 r8twmp rmcn2 l x: x 4k9+fyelb5,f86oon 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 resistance of a 100-W lighb t8/*ossvi -f.vm83am.mly v t bulb designed to be used in a 12.f s8y/va mtsmov lv b8*.3m-i0-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 resistae2rzq )yy -;p w1eh:yqr7ig :pnce of its heating element?y r2-ie:zrp : pg)qqeyh71;y w

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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 7 :ao fbxhye.* ee*5aaat $1/4 \; \Omega$. 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 rate-h8 i: t8pug3txx k nr6-kjqo hc.v91zd 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 dri-ou 9ec vk4asqmt:)0aw?

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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 use5jray0nsik44 d 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 runuf10,t *gcmhus 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 cost to operate a 25-W solderinws3nv :ok,l hclztb,01.a+p: u suo/c g iron for 8.0 hours, if energy covhnp,:ouaslt/ c+0o3,b lw1:ucsz.k 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 1005*f *lrj d.iwt-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 wbou ;nez:j5 i5zu3dhjr 27f6120-V line for 2.0 hours. How much heat energy is produced5e27u:5n ;dbw j6 3rifzozjuh?

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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. zqi8;:(4f0gadxt 6v4 m2 co e,bxtkvb How much energy does the battery store?;x:f bx4tgetibk0 8vo4 2mcaz6q, v (d

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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 atgo ao6wg2n 4; 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 o;t , n3*zps7pep .c /lh(tpj gs1yb/qqn 10 hours per day. Assuming the power company charges 10 cents for each kilowatt-hour of electricity used, estimate the/t(pztq,j.1e;*hgc lns pbp3s/ pyq7 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 monit9 32i0j s bvbzlfq7;nfor) is turned on 8.0 hours per day. If electricity costs 10 cents per kWh, hoj 7sv0iq l;fzb 3b92nfw 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 b:x7k 6f:9igeg zys hv.ill 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 t:k ieh.7g v6yfs:z9gxhe 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 7 9d v:l-yzxt6tw(fxhdrier operates on 240 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.) Whatt x9 -dylfhxt(6zv:w7 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 th1em6 bfdcv4,d(apb5u rough $8.0 \; \Omega$ 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 tj;p0 2mh/k30zb.ogynu s j5m $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% efficiency0g++vbmzm wzt63(vmw . How much current does it draw from a 120-t m(z0 w+gvb+wvzmm 36V 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 rm dwvj*g4rd)yu 7r.ou9z) fm/ ks current flows through this device?d9k7 yfz domuv jr).)/rgw 4*u

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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 frzaob9)z /c(a 120-V ac power source. What peak current flows trf zao(cz9)/bhrough 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 toi6m ma 8wh,yf+ a 120-V ac power source. What is the peak voltage across t m6imfw+,y8 hahis 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 wir)p8pgwv6 - c7xaah7s 2oyiz4j e is 0.081 inch. The maximum safe current it can carry 7pvo4chjx-)2g i7 8 sazw6ypa(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 centimeter of copper is $8.5 \times 10^{22}$.)

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