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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://autodiscover.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://autodiscover.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 t r lu6r) 83cx-pafi3bpransforming chemical energy into electrical energy is 8i)3x6clr bfparup -3called 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 bq4hc: 1 ddswo+ +*ewfthrough a wire's full cross section at any point per unit of time is refdqc w+fbdh *w14:s oe+erred 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 direction thaf0 ib+7,s ;cpyke8cm1m6rqs c t

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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 isl c6hwih7dt9lmyq22 :n kt q 4xn:s8;w 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 e- ch g 7pjwg(.tq,ved*1py8 rmeasure 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 wy4;2 3at*fgm pfnqai5ire is defined 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 i+izp ,3k)mtmqm bqjk(da1x n/- 7x.a8djll: ms

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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 deha xmq9q 2c*3rpends 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 z*wee54l emfvzzn1n0qd lex58 hiok s 7:+h:*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 1nywwr ;li, k4the length of the other. How do the resistivities of then, wwl1yi; r4kse 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 the length of the oth kul/;k5t (ddper. How do the resistances of these 5p/ku(td;d kl 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 ye iz:0ot.9tnz iw ;0o6ews .m7or2atwires. One has twice the cross-sectional area of the other. How do the resistances of these twoi:7 r2ow .y;sotn0ez 0a9mtew t6 .ozi 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. O/d 5hf*vyyg5bd h:e5l ,, qjxwne has twice the length and twice the cross-sectional area of the other. How do the resistances of these two wires compahxgvy,/5d5lfd,5qh yw:e *jbre?

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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 radi1hyd8 f58u(xvsmwvlb+ ,g-c q tx,oi 4us is doubled. By what factor does the resu cdfx4hyt8w1,vvlo5 s8 im(, +xgb-qistance 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 have0*fm-).g 2jw vaqpas -j xybt; compared to a 2.0 cm diameterjxygmb-j va0wa-) sq* ft;p2. 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)ttn,doq3ja )b rr4d ol ok-,1 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 coefficients of resistivityftv, 8p67 r1 fsjtaf;u

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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, 4gw)g of:nd dlow//l 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 equqa wjo.6s*7yvp oec):kn/f;i ivalent 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 voltazw6v 93qb a t243/pzh.n zfwjqge circuit is doubled, the power dissipated by that circuit wiljqt 3wv6w.apz4nfqhz2 39 b/zl

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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 cl .s /vufs)2hsnziz64onstant resistance is doubled, the power dissipated by that circuitn uv/ )4.f 6ih2sszlsz 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 f ;1 ua;du,.wzaxzne/u lowing is doubled, the power dissipated by that eud1zax/na;uu z;w., 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 resistance is hj*.pl.a; -tmvl-x6 rtj iy*mdoubled, the power dissipated b -jht-.lly;ixmr*m.tv6j* p ay 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 3tq3xk z -bt-oreduced by 5.0%. By what percentage is the power onq t -z3x3kto-b 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 iso u yre,n p r3py.h*j))6ojp)o 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 cu( zatk;mg9l u,( xdob8rrent of 3.0 A. One wire has twice the diameter of the other. The ratio of the drif 8z,x9d b(gm;atol(u kt 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 becomeor-: pgf1x sl )ng(qh0s essentially zero at very low temperatures are referred tgh xs-:p 1)nf(q0lgroo 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 :kzm /,2d yxjn8x *-zf6ciuerpgqr+; 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 passeo ar+v 6nmtw, mx8y/)ns through an electroplating apparatus in 2.0 min. What is the average cu8rwa,n/n +)oxmt6v myrrent?

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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 currenlw t961 fgyq; ;i)eaz/c:mv9m 1rpnjwt 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 if23wzax g wcv(3gpv)o62 eq6do $4.0 \times 10^{16} \; electrons$ 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 draws5g ar p+:mokd 0/*k2,qlblijq 13.5 A of current, has been left on for 10 min. What is the net number of agbqjdkl:kq2*,lm / p5 o+i 0relectrons 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 desired to deposit 40 mg of silver+p4hw.f as+cyw 7bg9p -a4uu j on a metal part by using a current of 2.0 A. How long must the curra4f9j ubpa4+hw-w +gy. u psc7ent 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 A to flow through a res5 kespe53iupz)y9y37ij r2 wi istance of )s9y 5u rw2ey3i i5ez7pipk j3330 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 acroz7tek 19av* ghss a 5.0-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 e6b7vgxu;8 vlj1y-eq 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 110os.r-f.5mbphue gv yib*/ *g- V draws 1.40 A of current. What is its resistances*mv/-h ybge*i f ug.-o5br p.?

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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 elecsyhgr -6ww0v,;w f8j ltrons flow through the wire - ww6w8 lv0h y,gjrf;sin
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 diametag -ac7 m+bb5s :gesy8er 0.40 inch? (The resistivity ofmyga:e 57- bsbc+8 gas 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 roh/u6jy :hfi6 kd 1.0 cm in diameter and 45 m long, if the resistivity :uh6j/ f6 kihyis $1.4 \times 10^{-8} \; \Omega \cdot m$?

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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 (resisti cn3 )lin/srg)vity $1.68 \times 10^{-8} \; \Omega \cdot m$) 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 (resistivhnf0;q(bx97 qb a l4vzity $1.68 \times 10^{-8} \; \Omega \cdot m$) 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 ohms. What is dp xwqz+oe-mz*mcc71-n09f oits 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 (the radius is gxjg )c 4y,(uk0.321 mm) nichrome wire if it is connected to a 12.0-V battery. (The resistivity of nichrkjux,cyg4(g )ome 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 recd;hu j4qnl:7h3 2hkantangular cross-section, 1.0 cm x 2.0 cm. What is the voltage drop 4 3qn:n ;dlhu h27ajkhalong 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 nichromglh ld(omnn8,y7x/ +i :nl y7qe 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 (resistivvxi;. d2(lmd kity $1.68 \times 10^{-8} \; \Omega \cdot m$) 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 res7fwn,ako b5-t5fotirl + *jt. istance 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 resist3qkmv x9 e4u6ae43h /enlqb c;ivity 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 resisy88z( gnssc-+im:. ebg th5o;y)wc vltance of the platinum wire is yc e yig) c+g5(osz.vsb88hm:l;wt- n $2.000 \; \Omega$ 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 through9 om-fr hwm8 ncdq404z6)y kgu 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 awin 7fg8cdu,zaj y23q/jh-( qt 1200 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 runncxko asc33lg:s:qkc f2l k38+ing on 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 light bulb desit.bfdbpgeilf , 2lay(8-v :388aru aogned to be used in a 120-V cir vif 8.reab uat:(abpf8-3gy ol,d8l2cuit?

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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 resistance of its heatycfnzc/l(ov p/ n:hkd15k,. k ing element?o/kld.zc p fykc/h 5(:n1,n vk

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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 r0 xh(wh e/s7 lcriek;3ated 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 at ko3.(kf5mn1r jd y+ujut :jj.$1/4 \; \Omega$. 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 1+bj1hl e-gu: ua2syo;20 V, what current 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 bu3ogzec o 4eu t30-j9*woner4plb. 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 on 110 V. )3oldgj:lehs,r+h vo,z v)j/ 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 hdlnc 0.; rwh2y. cc/t .0-*unqmge bnmours, if energy co l qbt*c nd 0nn. wmy.r2-;m.0/gccehusts $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 8.6k9c yo5/z )cs4 lm4um(r olk zpt;7zk0 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.y1+ osbg/(id p How much heat energy is proysib /p g(1od+duced?

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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 batwu z8kv2g0,x) qwsoo/tery store?,s0x )/gu2qw kzvow8o

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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 ,fq, lam)oy5ciron 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 p/3.b rd3benamf 8/ hkger day. Assuming the power company charges 10 cents for each kilowatt-hour of electricity used, estikb./a3bfm/en dh3 rg8mate 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 (comp/ p zg(g2:lm:k5 eqarhuter plus 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 annual/kg:5gl(e amz r:q2hp ly?

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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 inclutc, m0uqo*: sqay(kh-7 i1 gbaded 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 sq - (*cay mkqt1b uaogi,70:hto the 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 o;uff 4tb(zh, dn 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.) What effect will the repair have on the power dissipated in the heating eubzdtf( 4h, f;lement?

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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 thrj3bjzjh8 n* i7ough $8.0 \; \Omega$ 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 costuc+t0(fey b )zs $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.l u5180a 3dlkwnzosc8t/- y cf How much current does it draw from a 120-V line? 3azc-uo1 8dc0 stlwn5/klyf8 ($1 \; hp = 746 \; W$)

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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 9m2(io6 wfbr/ .od bvsto a 120-V ac power source. What rms current flows through this dio o2vwb f /(br6s9.mdevice?

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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 ybisreu .d y 9(558eraac power source. What peak current flows.ues (9dy8ryba 55rei through 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 nqf6t*htws w 0c4u q6:source. What is the peak voltage across this de6f4c *tw6:hsnwu qtq 0vice?

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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 copperz+jecg7c )dvg+i 0(x4fd wqr 5 wire is 0.081 inch. The maximum safe current it can cae0c4zdgj)d(r+7 x+qgw 5 fv icrry (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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