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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 electrzri/sks )g :gz5b/ne79.cpo y icity by transforming chemical energy into electrical e.y:i k gzsgz7)p/5e/s 9br ocnnergy 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 chari2di4il 1d akqz9 *chcqw*bg og,: ,p+ge that passes through a wire's full cross section at any point per unit of ti2,q :1iidz qcbi9 agghcpdw,+k o**l4me 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 direcyl.:(-e b; / (i9outpk9ktvp leitjm8tion 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 g. y(unh6b ywaitu9*:cc/q1h 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,vkh: )fx9j i1ul-w9m8mcg, x c ei;um 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 :v*b ;urx +futwire 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 w l7)e3nis5ul7k k *ym*tk+zwis

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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 dez- en mcvv50fpg27r 2ppends 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 lowest3jp b- hgsa-o9 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 the /2e k7pdp9 nimre dmie/p72n pk9sistivities of 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 wih9v;.q rwfx pfihu:/3xe5e) ures. One has twice the length of the other. How do the resistances of these t: hv5; eexxp9i . /rfhwqfu3)uwo 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 f,b7t ah d 0toykq7t n+h*(;tlwires. One has twice the cross-sectional area of the other. How dnyt 7d(ko+7 fha, ttbqh;tl 0*o the resistances 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 )9yu yn*eic,t. One has twice the length and twice the cross-sectional area of the other. How do the resi 9t,ycuyie*n)stances 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 wirek4 k5vmey dt8 ejdzca:,/wc:aw52 a6g is doubled and the radius is doubled. By what factor does the resistance change?2/y4ac wwzv m6da 5 dktegk:5:eac, j8

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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 hao:1r y t6apn2nve compared to a 2.0 cm diameter rod of the same length and made of the same n 6otpyr2na1: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 cw*/)psac r3el vk u)qwg*pa 7.ommon metals

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19#
 
单选题 ( 1.0 分) 切至整卷模式 搜藏此题  
  Negative temperature coeffh00c/xr8p*3dfhlk (l d sh7 6ls5wo veicients 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 equivalen bi7m/.2 cbzjpt 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 equivq 2m8h 63lmyizalent 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 ci/xq)bjj* eadpyoo24qi n49 2 arcuit is doubled, the power dissipated by td /bxoeo2 n*a4 i ajy94p2)jqqhat circuit 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 ;avtuvo7+ cn- a circuit of constant resistance is doubled, the power dissipated by that circuit 7cvao t-;unv+ 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 doubxu4s69 rzflg(06e wvd led, the power dissipated by that circuit wi w0vr4sg9de(fu zxl6 6ll

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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 wkklb0nbq8/o8n tj +hc 8l +(va circuit of constant resistance is doubled, the power dissipated by that circu8bb cv8(ontkl0hw + j +8k/nlqit 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 per.eec b/t7nj w3p 2b,wtcentage is the p / b327tetw .ew,pbcjnower 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 r 6:cpjfdd8qxo 2bc );zeferred 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 has twiae*upevp .3n 7s x)7; jswmme. z4pys;ce the diameter of the other. The ratio of the drift velocity in the small ya *)un;xm7vp.mp3s; zeej7w.sp4eser 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 resistii y5b+p tv6p )4r/pooqvity becomes essentially zero at very low temperatures aitbqpvo64 yo/5+ prp)re 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 cf h9eg5 i8k6z,:ae bzlharge 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. W5 .zdef;rg0 huhat is the augr;e .f0 5zhdverage 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 1x 5 27hfkang(v0 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 4-zdwc/+udsu84eods 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 left on for 10 min. fo8hk/ ,ptcd38 dc2db What is the net number of electrons that have pass 2ph8 dcd b/dt3fck8o,ed 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,yn8 u x.j)pyg* 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 the atomic weight of s*yxj8 .n )puygilver 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 requid5we;qox4k itdk1d/ *wu w0jut c7/p*red to cause 4.00 A to flow through a resistance of d5dpt/wwtx *01jkc7u/ kuwqd*ei; o 4 330 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 th8x1tzr l,g;kmrough 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 h c2cmsx2n7)68e ndieconnected 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 mh:, *lzxt (syV draws 1.40 A of current. What is its resistance?y z htxl*s,m:(

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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 resir a)nad1.*a.js jsu9istor. How many electrons flow through )n*uj. 1as.9jairds athe 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 resistanf : z8e0wp9wmm5pq2 bmce of 1.0 m copper wire of diameter 0.40 inch? (The resistivity of2p mmqpebw50zmfw9: 8 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, if tn m2 0,z8dwn9moq zm*kh* mnm 0zz,8mqkd9w on2e 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 wq d30r9wc 4j;a) jwbq(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 (resist5v n6 cijn:cll+5:pww 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 long651k oshc q+pd, 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-m long 22 gauge (the radius1expqg0 a2+o 0ojgq 3n is 0.321 mm) nichrome wire if it is connected to a 12.0-V battery. (The 0p1anoo+gg20jq exq3 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 2lv iss ta +7rhy4(ke;19w vzf50 cm long and of rectangular cross-section, 1.0 cm x 2.0 cm. s79ai+4t;e v yzwr5lk1(vhf sWhat is the voltage drop along 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 nichrome wire has a radius of 0.50 mm and a resistivity oflrm gu-2 ew xla116da6 $100 \times 10^{-8} \; \Omega \cdot m$. 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 (resistivityi 9i9j;p5zp/s s8znt i3h.ssi $1.68 \times 10^{-8} \; \Omega \cdot m$) 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 ofmn by x/3*ay0z $18 \Omega$ 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 resistivitylw3 lx+4h 42 tf-(m uxm)asqgw 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 eypj*wc34r*cto determine the melting point of indium. The resistance of the platinum wire 3ye** rpc 4cjwis $2.000 \; \Omega$ 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 throughe9hxjw l;f* t9vnp8nup0*p g* 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. What9 l64c 8xpmye52tli8 d-acudt 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 running on 1djus u6g;y4e* 10 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 lightqvj4)r8 ;9 eo z llazw-3-bbvg bulb designed to be used in a 120-V circuitvzzg 8rl 34l bv);e9j ob-qwa-?

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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/zq.evtr 4xumgo q7 01 at 120 V. What is the resistance of its heating elemenm7z0qt4x.quo r1/ev gt?

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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 t z1vg7ee(flko -1j*y 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 a( 112iqyu hvup 0ve1ymt $1/4 \; \Omega$. 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 tgyq/8qg qs* n plmk,)*)u+pmj5hx0zit 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, wha;qfw im5ybqd/*b64 g 3. oqpgat 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 ru msm5plzq 6u8vt5ke *(ns 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 2c9l wlk+ p+imrzkke-s* , +/da5-W soldering iron for 8.0 hours, if energy cost9,zscmw+al d+ *+/lrkkpki-es $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 8.05 tnmdx -c8tk9 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 augsqfkv 5h* k( 3y*tc( 120-V line for 2.0 hours. How much heat energy is producehqtus*5v gf( (*3cy kkd?

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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 1a.p2 nxvjwdp*so4l2 7q9jna5 60 A-h. How much energy does the battery store?72nn pj.2ov j9walx5p s* 4dqa

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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 atb r3e9wjpa(mj 23b+:e/gvt 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 covd.e6a dc x,m:mpany charges 10 cents for each kilowatt-hour of electricity usec:d6vax,d.e md, 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) is turned on 8.0 hours per day. Ifa,9t 8jfa 32rj2hjo zu electricity costs 10 cents per9rahz o28ujfj2,a3tj 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 a centrap yo .b+ / vg-:x*uqfj/brt(yfl 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. Ho+g /f :f-/ujvobx.ybr *qy(ptw 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 electr0t; f4-hlhzii )v m*,vw.5s phs1xuvoic drier operates on 240 V and generates heat at the rate of 2.1 kW. f0viwthusl;vm -, *xh)5s4zohv. 1pi 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 x,k/h+kq s*ppuu -)7xz0wko mthrough $8.0 \; \Omega$ 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 -m(lja i2h1sumhx; d *0w.bzv $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 m0 d3 g(fp9qb:w yet9dluch current dlye03g(9w d db9tq fp:oes 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-V ac power source. What z lq30 n-zi eas+lf-g0rms current flows through this 3g+ 0f-a siezlnlzq0-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 bmjxpxam03 5 (to a 120-V ac power source. What peak current flows3j x (5pmmx0ab 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 source. What is the peak voq,f(kzgd00 tp ltage across gtd,qzpk(f 00this 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 may1xg+a9z 8k psximum 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 the electrons? (The number of electron carriers in one cubic centimeter of copper ixy8gkz9 a 1p+ss $8.5 \times 10^{22}$.)

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