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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 transforming chemical ener ;c8f1sz-be4 ytw/h zfgy into electrical energy is callw ;/8-b e ty1s4fhfczzed 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'sv10auko4d ( ppnx6yfo i3m9.z full cross section at any point per unmoiokvz3( 9yup.0 nd1 ap6f x4it 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 curr3 gbv5: e /cd.1j mxo8 .l3kw6ncrocqzent 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 is the same zt/esc :zz1xd l499joas

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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,9fn4dnbgwb br-/cx r4d1(yxe, -jgy 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 ayx z1 . ,z pnr-hxox;qh6h28d9ca,clz 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 wirf dz.y.6xf+jr e 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 +,ua tg 9 ru g;w*w4m498ohwo8avjzlfzt94yqwire depends 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 lowestcyyg8: zsst6 h.d 33gv 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. O*p) tsy6;mpth q7e )iq.ip (jq gmv,4qne has twice the length of the other. How do the resistivities .) t)i,p*pq 4h(qqm;jy7t6gmeisvq pof 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 twdf rsf/87nku:ice the length of the other. How do the resistan7s :u/krf8d fnces of these 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 t1v7i;fcrxta/ he cross-sectional area of the other. How do the resistances of t 7vcir 1x;taf/hese 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. mz4 rveslbtk:x-mm 3 j01za;/ One has twice the length and twice the cross-sectional area of the other.zj x:z -0lm/a 1vsm 3ktmeb;4r How do the resistances 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 whats ;wsduw 2u1uikw95. s factor does the resistk9 uws1w u;i2uws5d.s ance 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 g 1xnm fdl3:lt/ vz-c4compared to a 2.0 cm diameter rod of the same lenglvt4nz d1/f3:g-lx cmth 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 p dvaev(q;(r/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 resistivitfd tg hbc+-5ds :lt.x.y

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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 equivalent9 e,my1acv4ryl t8+e v 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 equivalent zjb;q.du4ja *q+ o6cm 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 7+j ;f)f egk:tl;w;ef q88gqls moc4ipower dissipated by that c+;cjqfi;e;:4sg 8w mf )8egf7qlt okl ircuit 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-r9vk+;fh 3i.pw) clxp81 om rwaclp 5 of constant resistance is doubled, the power dissipated l+cplim9 cfo -p hrr.p)k;31x waw v85by 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 ,4;2 sic/-rrs ns doquwith constant current flowing is doubled, the power diss;4,-o/sns2dc sr i uqripated 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 reit b,owz a10o8wh +i7gsistance is doubled, the power dissipated bz 0woa i,w+78ghi1obty 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 reducecea0bz,k og gk5:e-e h9h2m1td by 5.0%. By what percentage is the power on a resistk1 h9agtc,bm o k gezh5e-02e:or 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 tt i ju3,,4ohvxo 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 carrying a current o *p jgyt02eo*lf 3.0 A. One wire has twice the diameter of the other. The ratio of the drift velocity ijoeg2*pt ly *0n 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: ;rm,da3hgoe at very low temperatures are referred to a,a;hmgored: 3 s

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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 i:5hclzh sf7;.qkja ..bhh 3shf 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 electroplating apparatus in 2.0 min. Wer;m i22a +vp0zv rbc0i6ja:shat is the averb06 zcai +p:eivs; m2ajrrv2 0age 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.+s mft +7ea8bd50 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 h rqfso ofi(gt5;1t*88 t xkq*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, hksw*l24 v7yv un4e) foas been left on for 10 min. What is the net number of e74 2f4oev) vksu*nwyl lectrons 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 ojt+mvj7bava7 iondm-uk q90fl ;;r: :n a metal part by using a current of 2.0 A. How long must the current be allowed to run to deposit this muc7-a ulof i0m vm;r;j+: n7vtqbdk9a:jh 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 axz i.sg5 ryo,, resistance of 330 sg r,zx5,.yio 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 acrosz6cpw7a2zwk qum)-l :s 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 con hdi4eybvaop.;gj.lf -j,7 ,vnected 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 current. What is its resistanck;xncu3,pr8m3 e e(naeem nr3ea(;3n,cxu8pk?

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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 electrons flow thxuk41n*s zl.+y+jwe 4yynq8h+0j k *w+xcoylrough the yj okusnelxy++y 8jzy1x k4.*4h*q++ wncl0wwire 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 0.40be kgr+ dl9j,+5b r7ej inch? (The resistivity j +b,9 d+5rgerbe lk7jof 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 long, imbj5+wigu hi (/rifrht9 n.p2 0rvz4*f the resistivity i+tvwug(fr/ 902 *z54 b hm hnjir.piris $1.4 \times 10^{-8} \; \Omega \cdot m$?

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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 (1io4j vykgx6pp-9d 0presistivity $1.68 \times 10^{-8} \; \Omega \cdot m$) 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 (rpgwot-.- 2hrg esistivity $1.68 \times 10^{-8} \; \Omega \cdot m$) 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, mee/;*x o*uy vklasures 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 curren)2tdt p p.qnk9t through a 10.0-m long 22 gauge (the radius is 0.321 mm) nichrome wkd)qpnp9tt2. ire if it is 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 of rectangular cross-section, 1.0 cm x 2.0 cm.i3ypwk m33o c, What is the voltage drop along its length when it carries 4000 A? (The resistiviywm33 3,kpc oity 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 nichromeafgvc7j j3a7m.xv 6el r63-ct*vvgn( 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 (resis 7 d-po g:(nik5lje*uvtivity $1.68 \times 10^{-8} \; \Omega \cdot m$) 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 resi-f7t sbpp8;d0 tpczs5 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 resi n4e.gnjdidp p.4o l.8stivity 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 mel(ni4 k7ds+5xbrh,preokv h* ,ting point of indium. The resistance of the platinum w5,+r (doh4 k*xkp bv,hen si7rire 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 throupsu h ew0ep:v. 7v-,xsgh 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 willmyi k9 3s1cg9a 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 vz1m hv2c3p *imuch 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 designed to ( 7p3rjl95*g pi-b+a .hey)vo vtu crebe used in a 120-V circuit?.c 9rrba3) jp-o7 uet(vl p*e5 +igyvh

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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 fz:,h shkw 158xcd d/ut y-v4eat 120 V. What is the resistance of its heating elemen/kz ,cdeh -uys1h d5 48wfvxt:t?

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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 at ao*hegt5q :.f 6ql ,8 r)wxbng$1/4 \; \Omega$. 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(by)dy p+/yj- insv-yd 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 i. 2m5tjuyorddh7 6 8s0jd4 5c*oml duft is used at 120 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 bu 39)cvlx fc8j. rjkn+ylb. 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 ironm n o),4g2:4h - nu tnerfv ,hr2h9+(ngohsqyu runs 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 tod*9s lq +gmca5 operate a 25-W soldering iron for 8.0 hours, if energy co+a*l c5q9 sdmgsts $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 34nn 3qdqqo+rixpdxh5v50p wgip: /gz/t)j0 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. How muchtd 85: iwznlf70zh9xh heat energy is produced?hwni7z8tfl dh 9xz :05

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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 : hfx7cbq 1fp012 V and 160 A-h. How much energy does the battery store?:7h0x cq bfp1f

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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 hrm) g4ify-p. uours?

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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 po3(ilsjgz.1r k wer company charges 10 cents for each kilowatt-hour of electricity used, estimatjls rk.3g 1i(ze 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) is turned on 8.0 hours pera p.;tu of+l gp-y-tz1rg7yi w2ds2k ; day. If electricity costs ywrus; giz-d1l2. g+to7fy;ta2kp p-10 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 the cost of running jry1s 4s(p wz0lb(zm1a central air-conditioning unit for 2.0 hr/day at 5000 W, and a series connection of ten 60 W light bulb4 lz w(br1pj ss0mz1y(s for 5.0 hr/day. How much did these items contribute to 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 owmw/x 5m m8j ) ht6gud/bvda2r 8c3zr+n 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 dissipv)+/23mxbuj8mc85azdghwwt r d6rm/ated 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 d.ou eack-f)934vywl $8.0 \; \Omega$ 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 sch: jn8tl b9-$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% efficienmmt m +8g48vhmcy. How much current does it draw from a 120-V line? g8mm4 +m8m thv ($1 \; hp = 746 \; W$)

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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 posg 78u ;kayi3iwer source. What rms current flows throky8si ug i3;7augh 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 a wyo6e,:y6 vmfj,ah) peak current flows throwy :m aj,6fe6 o,hvy)augh 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. W ipk u (/d hv;0hlazvl)dh,j60hat is the peak voltagi hzvlh)(ud6ap 0 h;lk ,0dvj/e across 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 incqv3b73/di/ :s ryz5qlry.joj7 k. x ymh. The maximum safe current it can carry (in order to prevent fire da5qy3lrsbj yy z3/v7/drqmj:x. ko 7. inger 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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