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习题练习:Physics Unit21: Electromagnetic Induction & Faraday's Law



 作者: admin   总分: 142分  得分: _____________

答题人: 匿名未登录  开始时间: 22年08月20日 21:29  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  
  All of the following are units of magnj(2cv0c vqpi-,9 bvpkit l bl.n;b.8metic flux except

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2#
 
单选题 ( 1.0 分) 切至整卷模式 搜藏此题  
  Faraday's law of induction statcr by:uky u028es that the $emf$ induced in a loop of wire is proportional to

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3#
 
单选题 ( 1.0 分) 切至整卷模式 搜藏此题  
  Doubling the number of loops of wire in a coil produces what kind of ch jee 6paau/9w.r *xfj4ange on the induced a*fj ae6x.eru9p/j4w $emf$, assuming all other factors remain constant?

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4#
 
单选题 ( 1.0 分) 切至整卷模式 搜藏此题  
  Doubling the strength of the magnetic 3ywn w /1vzun 6d nyrpex774ws ,-zyd7field through a loop of wire produces what kindd613,7prs-ynnyzw 7dey7 w w/ xu vn4z of change on the induced $emf$, assuming all other factors remain constant?

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5#
 
单选题 ( 1.0 分) 切至整卷模式 搜藏此题  
  Doubling the diameter of a loop of wire p5:e o gob0fcw cn1*.i)i(ar ((gyekqnroduces what kind of change on the indur:5wikey *fc(ocbn()a(e0 .1oq g i ngced $emf$, assuming all other factors remain constant?

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6#
 
单选题 ( 1.0 分) 切至整卷模式 搜藏此题  
  As a coil is removed from a magneticfxl 151v/(vuyod+ str u0jn9 c field an $emf$ is induced in the coil causing a current to flow within the coil. This current interacts with the magnetic field producing a force which

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7#
 
单选题 ( 1.0 分) 切至整卷模式 搜藏此题  
  According to Lenz's law, the direction of an induced current in a conductor ir7+m(2pfwo df5j z5swill be that which tends to produce which of the foo55ri 2 sfzd(7+wfjp mllowing effects?

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8#
 
单选题 ( 1.0 分) 切至整卷模式 搜藏此题  
  A circular coil lies flat on a horizontal table. A bar magnet is hel ide(jsg8ld*v4cq4 ,bd above its center with its north pole pointing down. The stationary magnet cel*s4qbvd48,gd(j i induces (when viewed from above)

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9#
 
单选题 ( 1.0 分) 切至整卷模式 搜藏此题  
  A circular coil lies flat on a horizontal table. A bar magnet is held above iqhh w65)i:je, npc8wa nq+ st4ts center with its north pole pointing down, and released. As it approaches the coil, the falling magnet inducehc8wq tnqs ) 6,hn+i a5j4pew:s (when viewed from above)

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10#
 
单选题 ( 1.0 分) 切至整卷模式 搜藏此题  
  A coil lies flat on a table top in a region where the magnetic field vector poihey nn7 p6b/o0xk; ,i +e:ufbpnts straight up. The magnetice /:fk ,p;xueni+obby0h pn67 field vanishes suddenly. When viewed from above, what is the sense of the induced current in this coil as the field fades?

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11#
 
单选题 ( 1.0 分) 切至整卷模式 搜藏此题  
  A coil lies flat on a level table top in a region where the m3fedap6/ t 3r*jcncspvb3 +.aagnetic field vector points straight up. The magnetic field suddenly grows stronger. When viewed from above, what is the direction ofa3apd+ 3n6v.tcb ep 3sfr*j/c the induced current in this coil as the field increases?

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12#
 
单选题 ( 1.0 分) 切至整卷模式 搜藏此题  
  A coil lies flat on a horizontal table top in a region where xg9p+,) y )b2n*u r,f egqozaibg6e/cf33irothe magnetic field points straight down. The magnetic field disappears so )bea*g if oqrx/zig33r e+n9y,,pcg )bf2u6uddenly. When viewed from above, what is the direction of the induced current in this coil as the field disappears?

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13#
 
单选题 ( 1.0 分) 切至整卷模式 搜藏此题  
  A long straight wire lies on a horizontal table and car*ts s5b;ehegiy1dn* l+,o7 rh3g i s4tries an ever-increasing current northward. Two coils of wh*ei5, dr4nst+bh s;eo3gylts7i* 1gire lie flat on the table, one on either side of the wire. When viewed from above, the induced current circles

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14#
 
单选题 ( 1.0 分) 切至整卷模式 搜藏此题  
  A bar magnet falls through a loop of wire with the north pole entehs;j6xfqp*ys4 tw xx9v n2: (xring first. As the north pole enters the wire, the qw jy;ts69spn:*x fx 4xh(x2vinduced current will be (as viewed from above)

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15#
 
单选题 ( 1.0 分) 切至整卷模式 搜藏此题  
  A circular loop of wire is rotated at constant angular speed about an axis whos r j01mjh *hep6)u8hbse direction can be varied. In a region where a uniform magnetic field points straight down, what must be the orientation of the loop'6) 1h*mp0jj sbrhuh e8s axis of rotation if the induced $emf$ is to be zero?

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16#
 
单选题 ( 1.0 分) 切至整卷模式 搜藏此题  
  A circular loop of wire is rotated at constant 4 hnb,6jd e)wdangular speed about an axis whose direction can be varied. In a region where a uniform magnetic field points straight down, what must be the orientation of the 64jehdn),wb dloop's axis of rotation if the induced $emf$ is to be a maximum?

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17#
 
问答题 ( 1.0 分) 切至整卷模式 搜藏此题  
State Faraday's law. 37dv),mnepidsus hlgmh8 or2y(y),3
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18#
 
问答题 ( 1.0 分) 切至整卷模式 搜藏此题  
State Lenz's law.
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19#
 
问答题 ( 1.0 分) 切至整卷模式 搜藏此题  
List the three ways thatc fzbrzhgic8:33kl : nuo0cy 14gdp02 an $emf$ can be induced in a loop of wire.
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20#
 
单选题 ( 1.0 分) 切至整卷模式 搜藏此题  
  A wire moves across a9/gvsn hl k *f(8k:fm 6gt9byx magnetic field. The $emf$ produced in the wire depends on

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21#
 
单选题 ( 1.0 分) 切至整卷模式 搜藏此题  
  A horizontal rod (oriented in the east-west direction) is moved nort nkt36 -4hwwbthward at constant 3 t46wtwbn-kh velocity through a magnetic field that points straight down. Make a statement concerning the potential induced across the rod.

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22#
 
单选题 ( 1.0 分) 切至整卷模式 搜藏此题  
  A horizontal metal bar rotates at an k mg,ahq9ilo d;/6x4 constant angular velocity $\omega$ about a vertical axis through one of its ends while in a constant magnetic field B that is directed down. The $emf$ induced between the two ends of the bar is

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23#
 
单选题 ( 1.0 分) 切至整卷模式 搜藏此题  
  An electric generator tmzc(rps;.rxfjy4b- 4 dbx-0 ogy* nc. ransforms

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24#
 
单选题 ( 1.0 分) 切至整卷模式 搜藏此题  
  A generator coil rotates through 60 revolutions each se+a( d8 g r vvf+oxm8x2,xcbk3k)dhv 2econd. The frequency of tdmv vo dxg(c8xb )evaxk2++,fk8 r2 h3he $emf$ is

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25#
 
单选题 ( 1.0 分) 切至整卷模式 搜藏此题  
  A transformer is a devie/ 0u fto(yhg d4,wyy,ce used to

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26#
 
单选题 ( 1.0 分) 切至整卷模式 搜藏此题  
  A transformer is a device thac h5kfp)bc0k*w (4 obrt

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27#
 
单选题 ( 1.0 分) 切至整卷模式 搜藏此题  
  In a transformer, if the secondary coil tl5-/u a/foccw/mmojw(b( z* contains more loops than the primary coil 5( * u wczmblf(atwc /o/m/jo-then it is a

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28#
 
单选题 ( 1.0 分) 切至整卷模式 搜藏此题  
  In a transformer, if the primary coil contains morb 8bu7gxt*v. laio53 w*n2agovpt :3re loops than the secondary coiu owgbl*a*vt.5 a:i3gt r b8o7 pv3nx2l then it is a

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29#
 
单选题 ( 1.0 分) 切至整卷模式 搜藏此题  
  In a transformer, the powegcpr0+0 g(c lqr input

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30#
 
单选题 ( 1.0 分) 切至整卷模式 搜藏此题  
  In a given LC resonant circuitul /pji d1,b4o,

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31#
 
单选题 ( 1.0 分) 切至整卷模式 搜藏此题  
  A resistor and an induc07 edykw 3 ;d5x+jt -ks*wpibntor are connected in series to an ideal battery of consta0jnk*d dy 3ebks+x-7; t5ipw wnt terminal voltage. At the moment contact is made with the battery, the voltage across the resistor is

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32#
 
单选题 ( 1.0 分) 切至整卷模式 搜藏此题  
  A resistor and an inductor are connected in series to an ideal battem:+c e3 bmyf3s,e*pc xry of constant terminal voltage. At the moment contact is made with the battery,33,cmfs*eex : +mypcb the voltage across the inductor is

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33#
 
单选题 ( 1.0 分) 切至整卷模式 搜藏此题  
  A series RL circuit with inductance L and resistance R is connectoyhkm z5op:2vnh*x9 2 ed to an $emf$. After a period of time, the current reaches a final value of 2.0 A. A second series circuit is identical except that the inductance is 2L. When it is connected to the same $emf$, what will be the final value of the current?

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34#
 
单选题 ( 1.0 分) 切至整卷模式 搜藏此题  
  A series RL circuit with inductance L and r. qxdn :;ycowy -;n c +(96s:uvnamxjtesistance R is connected to an $emf$. After a period of time, the current reaches a final value of 2.0 A. A second series circuit is identical except that the resistance is 2R. When it is connected to the same $emf$, what will be the final value of the current?

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35#
 
单选题 ( 1.0 分) 切至整卷模式 搜藏此题  
  A resistor and an inductor are connected in series to a batterb .bjq b7wgofxn 5 -488wixh)py. The time constant for the circuit represents the time required for the curj-8gh .f5nwi xx p78)bbqowb4rent to reach

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36#
 
单选题 ( 1.0 分) 切至整卷模式 搜藏此题  
  A resistor and an inductor are connected in series to a battery. The battery*:kgasox;-f e7 rwsj,a8qu -t is suddenly removed from the circuit. The time constant for of the circuit represents the time required for the current8;kat w 7qfs* j-sge,:uroax - to decrease to

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37#
 
单选题 ( 1.0 分) 切至整卷模式 搜藏此题  
  All of the following have theo tt-v yre7zxf2ftq5653t9*ska ll 0s same units except:

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38#
 
单选题 ( 1.0 分) 切至整卷模式 搜藏此题  
  A resistor is connected to an AC power supply. On this ciddhxei(r(.m w lb6m wdg-l:3.du/n/j rcuit, the current

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39#
 
单选题 ( 1.0 分) 切至整卷模式 搜藏此题  
  A pure inductor is connected to an AC7xg8mio1k *v f (zzdu/ power supply. In this circuit, the currentkifx7o d u*m8zvg (1z/

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40#
 
单选题 ( 1.0 分) 切至整卷模式 搜藏此题  
  The inductive reactance in an ac circuit changes by whij d8uem5d6 9iat factor when the frequency isi69dj8dime5 u tripled?

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41#
 
单选题 ( 1.0 分) 切至整卷模式 搜藏此题  
  If the frequency of the AC voltage across an ind5t1n(sa)qk9eko2epgq q8+ y6 b xvf i/uctor is doubled, the inductive reactance of that ind(xg82fqe+1 tq6ekab5p /i ny9s o)k qvuctor

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42#
 
单选题 ( 1.0 分) 切至整卷模式 搜藏此题  
  As the frequency of t )0b,oluixeqq 7 +kwrg.m39t vhe AC voltage across an inductor approaches zero, the induc xi,ew 0q.q79k uvo3tr+l)m bgtive reactance of that coil

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43#
 
单选题 ( 1.0 分) 切至整卷模式 搜藏此题  
  A pure capacitor is connected to an AC power supply. In this ht1i gh.zc 75 *odib gr1drld61u8* obcircuit, the curre1*hidd5ul 1crdr*go h7it.b61ogb z 8nt

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44#
 
单选题 ( 1.0 分) 切至整卷模式 搜藏此题  
  The capacitive reactance in an ac circuit changes by what x u1sb3c do(o)factor when the frequency is tripxo o )s31c(dbuled?

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45#
 
单选题 ( 1.0 分) 切至整卷模式 搜藏此题  
  As the frequency of tha :zg1 et95xqcwhai9rj+7 f:ne AC voltage across a capacitor approaches zero, the capacitive reactance ofa9gaj+: f1zxc9n: teihw 7q5 r that capacitor

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46#
 
单选题 ( 1.0 分) 切至整卷模式 搜藏此题  
  What is the phase angle between the vn4n zbt,w;u7 ( 9rqevuoltages of the inductor and capacitor in a RLC series circuit?n( r utw4veq,b7z9un;

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47#
 
单选题 ( 1.0 分) 切至整卷模式 搜藏此题  
  The power factor of an RLC circuit is defi-hp-e pa/cxjzqw d6 4(ned as $\cos M = R/Z$, but the phase angle can also be calculated from .

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48#
 
单选题 ( 1.0 分) 切至整卷模式 搜藏此题  
  Consider an RLC circuit. The impedance of the cir -2qeb5tziu+lt1k* +n lmn,fn i j;k6zcuit increases if R increases. When is ek,zt+u15-fnt2in lb l mni ;zq*6 kj+this statement true?

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49#
 
单选题 ( 1.0 分) 切至整卷模式 搜藏此题  
  Consider an RLC circuit. The impedance of thoo.ekgji;+fo g (,vqf- sjm91e circuit increases if $X_L$ increases. When is this statement true?

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50#
 
单选题 ( 1.0 分) 切至整卷模式 搜藏此题  
  Consider an RLC series c f8ug3j.p k(ehb/re;yircuit. The impedance of the circuit increases if $X_C$ increases. When is this statement true?

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51#
 
单选题 ( 1.0 分) 切至整卷模式 搜藏此题  
  If the inductance and the capacitance both double in an LRC seribp xvp26*stg3ln5)gq es circuit, the resonant frequqngpvx) gst 32*lp 65bency of that circuit will

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52#
 
单选题 ( 1.0 分) 切至整卷模式 搜藏此题  
  Consider an RLC circuit that is driven by an gjr0if;.l7q7o:sv v b0bw7 v mAC applied voltage. At resonance,

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53#
 
单选题 ( 1.0 分) 切至整卷模式 搜藏此题  
  Resonance in a seriesl8nuy)hu-nhb 18xwf : RLC circuit occurs when

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54#
 
单选题 ( 1.0 分) 切至整卷模式 搜藏此题  
  A flux of $4.0 \times 10^{-5} \; Wb$ is maintained through a coil for 0.50 s. What $emf$ is induced in this coil by this flux?

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55#
 
单选题 ( 1.0 分) 切至整卷模式 搜藏此题  
  A circular loop of radius 0.(a j85p+5wtrhk wch7faub( ;m 10 m is rotating in a uniform magnetic field of 0.20 +c5f wabpj(k;a tw87u hh5(rmT. Find the magnetic flux through the loop when the plane of the loop and the magnetic field vector are parallel.

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56#
 
单选题 ( 1.0 分) 切至整卷模式 搜藏此题  
  A circular loop of radius 0.10 m is rotating in a4rko1 ( 6xkzij uniform magnetic field of 0.20 T. Find the magnetic flux through the loop whenzxkk1j6i( r4o the plane of the loop and the magnetic field vector are perpendicular.

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57#
 
单选题 ( 1.0 分) 切至整卷模式 搜藏此题  
  A circular loop of radius 0.10 m is rotating in ax0ufds :af;obdly 6/ 021uld m uniform magnetic field of 0.20 T. Find the magnetic flux through the loop when the plane of the loop and the magnetic field vector are at andlu y6l 1f s:mu20fdb a0d;/ox angle of $30^{\circ}$.

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58#
 
单选题 ( 1.0 分) 切至整卷模式 搜藏此题  
  The cross-sectional area of an adjuqrik3;)rh uet 9glf (g62xq)qstable single loop is reduced from $1.0 \; m^{2}$ to $0.50 \; m^{2}$ in 0.10
s. What is the average $emf$ that is induced in this coil if it is in a region where B = 2.0 T upward, and the coil's plane is perpendicular to B?

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59#
 
单选题 ( 1.0 分) 切至整卷模式 搜藏此题  
  The flux through a coil changes uj):yie)0 (z gyr,q8 pahp9zxk31 dhb from $4.0 \times 10^{-5} \; Wb$ to $5.0 \times 10^{-5} \; Wb$ in 0.10 s. What $emf$ is induced in this coil?

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60#
 
单选题 ( 1.0 分) 切至整卷模式 搜藏此题  
  A coil is wrapped with 200 turns o2itx 91:9k aqa2 e-mgk ijer;bm;teq, .f+g gaf wire on a square frame with sides 18 cm. A uniform magnetic field is applied perpendicular to tg ea :gx2ak-beq 2q,mia k99.i; +gf1ertjtm ;he plane of the coil. If the field changes uniformly from 0.50 T to 0 in 8.0 s, find the average value of the induced $emf$.

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61#
 
单选题 ( 1.0 分) 切至整卷模式 搜藏此题  
  A square coil of wire with 15 turns and an are*mpzx2y 6kc8z (hze3ea of $0.40 \; m^{2}$ is placed parallel to a magnetic field of 0.75 T. The coil is flipped so its plane is perpendicular to the magnetic field in 0.050 s. What is the magnitude of the average induced $emf$?

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62#
 
单选题 ( 1.0 分) 切至整卷模式 搜藏此题  
  A coil of 160 turns and ar qme0fuq0y y( ;k.ie,iea $0.20 \; m^{2}$ is placed with its axis parallel to a magnetic field of 0.40 T. The magnetic field changes from 0.40 T in the x-direction to 0.40 T in the negative x-direction in 2.0 s. If the resistance of the coil is 16 W, at what rate is power generated in the coil?

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63#
 
单选题 ( 1.0 分) 切至整卷模式 搜藏此题  
  An airplane with a wing span of 60 m -a/ v;ac 57clvswmi0sflies horizontally at a location where the downward component of the Earth's ma0a/svwm75 ;l -cicvs agnetic field is $6.0 \times 10^{-5} \; T$. Find the magnitude of the induced $emf$ between the tips of the wings when the speed of the plane is 225 m/s.

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64#
 
单选题 ( 1.0 分) 切至整卷模式 搜藏此题  
  A horizontal metal bar that is 2.0 m long rotates at a constant angu js w0v6ix,m+mlar velocity of 2.0 rad/s about a vertical axis through one of its ends while in a constm6v msi0 x,j+want magnetic field of $5.0 \times 10^{-5} \; T$. If the magnetic field vector points straight down, what $emf$ is induced between the two ends of the bar?

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65#
 
单选题 ( 1.0 分) 切至整卷模式 搜藏此题  
  The coil of a generator has 50 loops and a cross-sectional areaow ,hb i*4fkjflb 1u u4o(q9i:dnny7, of $0.25 \; m^{2}$. What is the maximum $emf$ generated by this generator if it is spinning with an angular velocity of 4.0 rad/s in a 2.0 T magnetic field?

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66#
 
单选题 ( 1.0 分) 切至整卷模式 搜藏此题  
  An AC generator consists of 100 t)e dman-m g4*f0q2dx nurns of wire of area $0.090 \; m^{2}$ and total resistance 12 W. The loops rotate in a magnetic field of 0.50 T at a constant angular speed of 60 revolutions per second. Find the maximum induced $emf$.

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67#
 
单选题 ( 1.0 分) 切至整卷模式 搜藏此题  
  An AC generator has 8 +vqe q++1nqnsh9 i3yh3vj rd10 rectangular loops on its armature. Each loop is 12 cm long and 8 cm wide. The armature rotates at 1200 rpm about an axis parallel to the long side. If the loop rotates in a uniform magnetic field of 0.30 T, wr3s+n+qn qv1iyd hv eq+3 9jh1hich is perpendicular to the axis of rotation, what will be the maximum output voltage of this generator?

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68#
 
单选题 ( 1.0 分) 切至整卷模式 搜藏此题  
  An AC generator consists of 100 turns of wisk /x57uwh:z sre of area $0.090 \; m^{2}$ and total resistance 12 W. The loops rotate in a magnetic field of 0.50 T at a constant angular speed of 60 revolutions per second. Find the maximum induced current.

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69#
 
单选题 ( 1.0 分) 切至整卷模式 搜藏此题  
  Suppose that you wish to construct a simple AC generator with a5 *ift5cl4z14xku yrpn output of 12 V maximum when ri z1p 45k cxyurf4l5t*otated at 60 Hz. A magnetic field of 0.050 T is available. If the area of the rotating coil is $100 \; cm^{2}$, how many turns are needed?

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70#
 
单选题 ( 1.0 分) 切至整卷模式 搜藏此题  
  You are designing a generato3 vou * cwfznots1hb6re6d5 9xp 963spr with a maximum $emf$ of 8.0 V. If the generator coil has 200 turns and a cross-sectional area of $0.030 \; m^{2}$, what would be the frequency of the generator in a magnetic field of 0.030 T?

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71#
 
单选题 ( 1.0 分) 切至整卷模式 搜藏此题  
  The windings of a DC motor have a resistance of 6.00 W. ovth2u 4m;g;):0n ;hfygb ykxThe motor operates on $120 \; V$ AC, and when running at full speed it generates a back $emf$ of 105 V. What is the starting current of the motor?

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72#
 
单选题 ( 1.0 分) 切至整卷模式 搜藏此题  
  The windings of a DC motor have a resistu2iqs.ny+ f7 zance of 6.00 W. The motor operates on 120 V AC, and when running at full speed it genera2n. isu7 yfqz+tes a back $emf$ of 105 V. What current does the motor draw when operating at full speed?

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73#
 
单选题 ( 1.0 分) 切至整卷模式 搜藏此题  
  A DC motor of internal resisj , s6*v6 co9,, lvs enk*nwxoyobh-g6tance 6.0 W is connected to a 24-V power supply. The operating current is 1.0 A. What iw*,j x 66gbovn * ok-o,hsvnly ,cs69es the start-up current?

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74#
 
单选题 ( 1.0 分) 切至整卷模式 搜藏此题  
  A DC motor of internal resistance 6.0 W is connected to a 24-V pmx zf +)ogt5l l/j.c8kower supply. The operating current is 1.0 A at full speed. Wha cjl8f 5 zl/.k+o)xtmgt is the back $emf$ when the motor is running at full speed?

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75#
 
单选题 ( 1.0 分) 切至整卷模式 搜藏此题  
  A DC motor of internal resistance 6.0 W is connected to a 24-V power supply. Th lhk 0hyl08ye7e operating current is 1.0 A at full speed. What is the bake0yl h8 70hylck $emf$ when the motor is running at half speed?

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76#
 
单选题 ( 1.0 分) 切至整卷模式 搜藏此题  
  A step-down transformer ik/f p,;h/fpar . lq1tim.t*zps needed to reduce a primary voltage of $120 \; V$ AC to $6.0 \; V$ AC. What turns ratio is required?

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77#
 
单选题 ( 1.0 分) 切至整卷模式 搜藏此题  
  2.0 A in the 100-turn primary of a transformer causes 14 Atb c+wxzze : -gx, 0b9;-exboq to flow in the secondary. How many turns are in the sebxzwt0+;:qce 9g-b,xoz bex -condary?

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78#
 
单选题 ( 1.0 分) 切至整卷模式 搜藏此题  
  In a transformer, how many turns are necessa5dx gt4,gt38rjxtx:n (s8z twry in a 110-V primary if the 24-V seconda8zt,t gx( 4r xtgjtx5nd w8s:3ry has 100 turns?

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79#
 
单选题 ( 1.0 分) 切至整卷模式 搜藏此题  
  An transformer consists of a 500-turn primary coilq2t d-bbj6t2;vjn 3t w and a 2000-turn secondary coil. If t 3w; -qjtdnvjtt2bb2 6he current in the secondary is 3.0 A, what is the current in the primary?

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80#
 
单选题 ( 1.0 分) 切至整卷模式 搜藏此题  
  5.0 A at 110 V flows in the primary of a transf.m j8zsuj( ql:)i(* klkakl-mormer. Assuming 100% efficiency, how many amps at 24 V can flow in the secondar( j8quk lkm:.ij*()lkm z -slay?

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81#
 
单选题 ( 1.0 分) 切至整卷模式 搜藏此题  
  The secondary coil of a neon sign transformer provides 7500 V at 103bam.64 dff zc.0 mA. The primary coil operates on 120 V. What does the primar af6cbd .zfm34y draw?

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82#
 
单选题 ( 1.0 分) 切至整卷模式 搜藏此题  
  An ideal transformer has 60 turns on its pri-aawzy2swphm ;v4 9f ;mary coil and 300 turns on its secondary coil. If 120 V y2pwh;s -;am4z9wf vaat 2.0 A is applied to the primary, what voltage is present in the secondary?

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83#
 
单选题 ( 1.0 分) 切至整卷模式 搜藏此题  
  An ideal transformer has 60 turns on its primary coil andae.;ei3 etle .id +gc: 300 turns on its secondary coil. If 120 V at 2.0 ce e+;ed:g iie3. al.tA is applied to the primary, what current is present in the secondary?

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84#
 
单选题 ( 1.0 分) 切至整卷模式 搜藏此题  
  The primary of a transformer has 100 turns and its secondary has 200 turns. u:zd k1ck0mgj r46yqp c/2o6 k If the input current at the primary i1cku46/ 2j dzo :c rkkmq60gyps 100 A, we can expect the output current at the secondary to be

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85#
 
单选题 ( 1.0 分) 切至整卷模式 搜藏此题  
  The primary of a transformer has 100 turns and its sewf t ybcd v28q17z7ba9cu, j.bcondary has 200 turns. If the inp,t27. 7cb jvd yfzabq9bcuw18ut voltage to the primary is 100 V, we can expect the output voltage of the secondary to be

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86#
 
单选题 ( 1.0 分) 切至整卷模式 搜藏此题  
  The primary of a transformer hass(7s5v xq764kcn 4elqxr cbt9 100 turns and its secondary has 200 turns. If the power input to the primary is 100 W, we can expect the vc s q q79xtnrbc4ls5e7k(46xpower output of the secondary to be (neglecting frictional losses)

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87#
 
单选题 ( 1.0 分) 切至整卷模式 搜藏此题  
  A generator produces 60 A of cu8--mxmv);*f ala ds7it;/d tdggtz 2yrrent at 120 V. The voltage is usually stepped up t aztdg;gl- t-x m8;yd t*v)im7as2/dfo 4500 V by a transformer and transmitted through a power line of total resistance 1.0 W. Find the number of turns in the secondary if the primary has 200 turns.

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88#
 
单选题 ( 1.0 分) 切至整卷模式 搜藏此题  
  A generator produceservfn(. : ot-t 60 A of current at 120 V. The voltage is usually stepped up to 4500 V by a transformer and transmitted through a power line of total resiso-.vt(nf ter:tance 1.0 W. Find the percentage power lost in the transmission line.

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89#
 
单选题 ( 1.0 分) 切至整卷模式 搜藏此题  
  A generator produces 60 A of cu gg-s/g0pi+og.ewb:w rrent at 120 V. The voltage is usually stepped up to 4500 V by a transformer and transmitted through a power line of total resistance 1.0 W. Find the percentage pow-0bi:gpww.gg /os e+ ger lost in the transmission line if the voltage is not stepped up.

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90#
 
单选题 ( 1.0 分) 切至整卷模式 搜藏此题  
  A power transmission line 50 km long has a total resistance of 0.60 W. g(ot mktpqi5, 8cqz1:A generator produces 100 V at 70 A. In order to reduce energy loss due to heating of the transmission line, the voltage is stepped up with a transformer with a turns ratio om5pk i,8qctzto: (qg1 f 100:1. What percentage of the original energy would be lost if the transformer were not used?

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91#
 
单选题 ( 1.0 分) 切至整卷模式 搜藏此题  
  A power transmission line 50 km long hasc9+,+jry2 f xc mginy;mv48u 53 vzlnx a total resistance of 0.60 W. A generator produces 100 V at 70 A. In order to reduce energy loss due to heating of the transmission line, the voltage is stepped up with a transformer with a turm un vm9 3i;crjzn52x,f+4 cv8 lyy+gxns ratio of 100:1. What percentage of the original energy is lost when the transformer is used?

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92#
 
单选题 ( 1.0 分) 切至整卷模式 搜藏此题  
  100 kW is transmitted down a 6-W line at 1000 V. How much lessjw6e 1a p7gx1d power would be lost if the power were transmitted at 3000 V instead ofej agw71x d16p at 1000 V?

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93#
 
单选题 ( 1.0 分) 切至整卷模式 搜藏此题  
  The output of a generator is 440 V at 20 /zip2+k2d eydA. It is to be transmitted on a line with resistance of 0.60 W. To what voltage must the generator output bp2zd+2ei k d/ye stepped up with a transformer if the power loss in transmission is not to exceed 0.010% of the original power?

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94#
 
单选题 ( 1.0 分) 切至整卷模式 搜藏此题  
  A 4.0-mH coil carries a current of 5.0 A. How much energy is stored in the con za*b p k;57;wl-kjnxil's mnwn 5l; ;a-jkk7zb*p xagnetic field?

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95#
 
单选题 ( 1.0 分) 切至整卷模式 搜藏此题  
  A simple RL circuit contains a 6.0-W resistor and an 18-H inductor. i4 n /h/op-q/wfs o*p c,8qtgmWhat is this circuit's time ctc8f/4hn qwo,p//*gqipso m -onstant?

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96#
 
单选题 ( 1.0 分) 切至整卷模式 搜藏此题  
  What is the peak voltage in an AC circuit where the rms+i0k- fc +awl*-odlv w voltage is 120 V?

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97#
 
单选题 ( 1.0 分) 切至整卷模式 搜藏此题  
  A 150-W lamp is placed into a 120-V AC outlet. What is the peak curre ka pb3g6/pbke*h4 w7mnt?

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98#
 
单选题 ( 1.0 分) 切至整卷模式 搜藏此题  
  A 150-W lamp is placed into a 120-V AC outlet. What is tt9(ikxuw/n 1meg2if6 so h0- phe resistance of the lam-wux9(2mgfei6it1o snhk0/ pp?

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99#
 
单选题 ( 1.0 分) 切至整卷模式 搜藏此题  
  A 10-W resistor is connected to ny: w63-f6 e8zlutohua 120-V ac power supply. What is the peak current through the ro-:63n8flw6uet yhzu esistor?

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100#
 
单选题 ( 1.0 分) 切至整卷模式 搜藏此题  
  A 10-W resistor is connected to a 120-V ac power supply. Whc09khw7m v 3qc6xhf 3mat is the power dissipated in th ch kfcm36w q3m90vx7he resistor?

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101#
 
单选题 ( 1.0 分) 切至整卷模式 搜藏此题  
  The current through a 50w0 3jif2yk 6(uf3p;tfhf b vm.-W resistor is $I = 0.80 \sin (240 t)$. What is the rms current?

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102#
 
单选题 ( 1.0 分) 切至整卷模式 搜藏此题  
  The current through a xvmjdga,(a(:icf:n b3, kx 2m50-W resistor is $I = 0.80 \sin (240 t)$. At what frequency does the current vary?

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103#
 
单选题 ( 1.0 分) 切至整卷模式 搜藏此题  
  The current through a 5t j;-mu2bji 0m0-W resistor is $I = 0.80 \sin (240 t)$. How much power on average is dissipated in the resistor?

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104#
 
单选题 ( 1.0 分) 切至整卷模式 搜藏此题  
  What is the reactance of a 1.0-mH ind +tniq;n-)xlhe3b cn 0uctor at 60 Hz?

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105#
 
单选题 ( 1.0 分) 切至整卷模式 搜藏此题  
  What is the inductive reactance of a 2.50-m6i;rcor6qj/y eun gn,w+)xh- H coil at 1000 Hz?

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106#
 
单选题 ( 1.0 分) 切至整卷模式 搜藏此题  
  At what frequency will a 14.0-mH y b 6dut-t02c k),p/oa ,dbrmmcoil have 14.0 W of inductive reactance?

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107#
 
单选题 ( 1.0 分) 切至整卷模式 搜藏此题  
  What inductance is necessary for 157 W of inductive reactance at 1000 2jhwdcs,hgljn 3 (jw)jk u*79Hz?

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108#
 
单选题 ( 1.0 分) 切至整卷模式 搜藏此题  
  What current flows in a 60-mH inductor when 120 V AC at a frequency of 2v ,vn/asf.wlwk (lj,fg (2f1z0 kHz is applied w al/ks(2( fn1 ff,.lw,vgvzjto it?

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109#
 
单选题 ( 1.0 分) 切至整卷模式 搜藏此题  
  What is the current through a 2.50-mH coil due to a 110-V, 60.0 Hz source?9rm;/hns+u)mfuo 7 ys

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110#
 
单选题 ( 1.0 分) 切至整卷模式 搜藏此题  
  What is the capacitive reactance of a 4.7-1s-n;snwk+0t fdu )r 4tt.8u teu iy.smF capacitor at 10 kHz?

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111#
 
单选题 ( 1.0 分) 切至整卷模式 搜藏此题  
  What size capacitor is needed to have 50 W of capacitive reactnicx,6(nai , :e.cvqcance at 10 kHz?

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112#
 
单选题 ( 1.0 分) 切至整卷模式 搜藏此题  
  At what frequency doejdd(9 jht+dd 2lr8u8t s a 10-mF capacitor have a reactance of 1200 W?

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113#
 
单选题 ( 1.0 分) 切至整卷模式 搜藏此题  
  At what frequency will the capacitive s1c 3l.nbctk9reactance of a 0.010-mF capacitor be 100 W9 b clt1n.3kcs?

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114#
 
单选题 ( 1.0 分) 切至整卷模式 搜藏此题  
  What is the current through a 0.0010-mF capactf-skm,dv0 lw js *sdy8:f0i8itor at 1000 Hz and 5.0 V?

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115#
 
单选题 ( 1.0 分) 切至整卷模式 搜藏此题  
  What is the impedance of an ac series circo* /z:k0 vre/;mmtuq duit with 12.0 W resistance, 15.0 W inductive reactance, and 10.0 W capacitive re*e0z:ko;tm/r uq/d mvactance?

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116#
 
单选题 ( 1.0 分) 切至整卷模式 搜藏此题  
  What is the total impedance at 1500 Hz if a 100-W resistor, 20-mH coil, qmn,x .x,wvo6and 1.0-mF capacitor are connected in ser6w,nq,v m.oxx ies?

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117#
 
单选题 ( 1.0 分) 切至整卷模式 搜藏此题  
  What is the phase angle at 1500 Hz if a 100-W resistor, 20-mH coil, and 1.0-mF c9v+k4unq ,e*rvv ( t. rncnqsif(p54vapacitor are connected in seriekn.5ir +evnfq4 ,(pt(r9sv cnv *v 4qus?

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118#
 
单选题 ( 1.0 分) 切至整卷模式 搜藏此题  
  If a 1000-W resistor is convm ps ,xft2 lgt0i16c6nected in series with a 20-mH inductor, what is the impedancet6pf0xg 6,12icstm v l at 1000 Hz?

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119#
 
单选题 ( 1.0 分) 切至整卷模式 搜藏此题  
  If a 1000-W resistor is connected in series with a 20-mH inductof:klaa lj 4dln:)of/n (lj:-dr, what is the phdfa/(ldfoa n4j:n kl j ):-l:lase angle at 1000 Hz?

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120#
 
单选题 ( 1.0 分) 切至整卷模式 搜藏此题  
  What resistance is needed in a series circmgvuy v; ;rvkisl1..6uit with a 20-mH coil and 1.0-mF capacitor for a total impedance of 100 W at 15v..ysr6gum ;kvl 1vi ;00 Hz?

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121#
 
单选题 ( 1.0 分) 切至整卷模式 搜藏此题  
  Which of the following capacitances is needed in series wit5cn0nfd rcv g4/zj) r1h a 100-W resistor and 15-mH coil to get a total impedance of 110 W at 2005jg c14r/)vrn ndcz0 f0 Hz?

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122#
 
单选题 ( 1.0 分) 切至整卷模式 搜藏此题  
  What resistance must be put in series with a 450-mH inductor at 5000 c kv42 u)of9zlHz for a total impedance of 40000 W) fc vzu49l2ko?

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123#
 
单选题 ( 1.0 分) 切至整卷模式 搜藏此题  
  What inductance must be put in ft5na: tg,ff1series with a 100-kW resistor at 1.0-MHz for a total impfg:t5t1fan,f edance of 150 kW?

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124#
 
单选题 ( 1.0 分) 切至整卷模式 搜藏此题  
  A 10-W resistor is connected in series with a 20-mF capacitor. What is the 5ml82cs jjuy7impedances8j7u5y cj2lm at 1000 Hz?

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125#
 
单选题 ( 1.0 分) 切至整卷模式 搜藏此题  
  What resistance is needed in series with h4-p4vzm9i ior i,5tx a 10-mF capacitor at 1.0 kHz for a total impedh,t94iim rvoz- i45pxance of 45 W?

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126#
 
单选题 ( 1.0 分) 切至整卷模式 搜藏此题  
  What resistance is neede2l3bu916cjhk ebln5i qtla,-a23tk kmmt 7 z +d in series with a 10-mF capacitor at 1.0 kHz for a phase ,+amq 6kh -k 3u1itltz t22makbnlbjc75e9l3angle of $40^{\circ}$?

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127#
 
单选题 ( 1.0 分) 切至整卷模式 搜藏此题  
  What capacitance is needed ao x ,t2bga69win series with a 30-W resistor at 1.0 kHz for a totalg,x62a wtbo9a impedance of 45 W?

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128#
 
单选题 ( 1.0 分) 切至整卷模式 搜藏此题  
  A 10-W resistor is in series with a 100-mF capacitor at 120 Hz.cy 3bvq2g0+ry What is the phase angq gbyc+yv032rle?

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129#
 
单选题 ( 1.0 分) 切至整卷模式 搜藏此题  
  What current flows at 5.0 V and 1500 Hz if a 100-W resistor, 20-mH coil,s md;f qfwc11( and 1.0-mF capacitor are connected in sericwq ms1ff1d( ;es?

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130#
 
单选题 ( 1.0 分) 切至整卷模式 搜藏此题  
  A series RLC circuit consists of a 100-W resistor, a 10.0-mF capacx4,oe;d)z z*f ussfy8: 6nzh*gv2blritor, and a 0.350 f , ns xru;slz2*v8doe6h)gy:zbf*4z-H inductor. The circuit is connected to a 120-V, 60-Hz power supply. What is the rms current in the circuit?

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131#
 
单选题 ( 1.0 分) 切至整卷模式 搜藏此题  
  A resistance of 55 W, a-kmt,4,fx/ye74 rrmyuk/ynv capacitor of capacitive reactance 30 W, and an inductor of inductive reactance 30 W are connected in series to a 110-V, 60-Hz power source. What current flows in this circkmn-xvyy ,ym4 ,fue4trk //7r uit?

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132#
 
单选题 ( 1.0 分) 切至整卷模式 搜藏此题  
  What is the phase angle for a series RLC circuito ,dr5nul0 x/b containing a 50-W resistor, a 10-mF capacitor, and a 0.45-H inductor, when connected to a 60-Hz power supply?l/bx 0r n5ud,o

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133#
 
单选题 ( 1.0 分) 切至整卷模式 搜藏此题  
  What inductance is necessary in series with a 500-W resist7vtqoe; sw8-d or for a phase angle ov w7qste;d8 -of $40^{\circ}$ at 10 kHz?

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134#
 
单选题 ( 1.0 分) 切至整卷模式 搜藏此题  
  A series RLC circuit has R = 20.0 W, L = 200-3t5wej unq,)yn z8)osp rx1 m-mH, C = 10.0 mF. At what frequency should the circuit be driven in order to have maximum power transferred from the driving so q 83 njyzowpx),-nu )5t1smerurce?

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135#
 
单选题 ( 1.0 分) 切至整卷模式 搜藏此题  
  What is the power output in an ac series circuit with 12.0 W resi8uok1kk9 a0hulk:j 7 fz hpe1-stance, 15.0 W inductive reactance, and 10.0 W capacitive reactance, when the circuit is conn upk-9kh ko8k1zf 0ahu lje17:ected to a 120-V power supply?

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136#
 
单选题 ( 1.0 分) 切至整卷模式 搜藏此题  
  The phase angle of an A*d+y5iyo5syf C circuit is $63^{\circ}$. What is the power factor?

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137#
 
单选题 ( 1.0 分) 切至整卷模式 搜藏此题  
  An ac series circuit has an impedance 0t ykgg rk ,xg)0/6mxgof 60 W and a resistance of 30 W. What is t06ygk0r tx/ ,xk)gggmhe power factor?

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138#
 
单选题 ( 1.0 分) 切至整卷模式 搜藏此题  
  What is the power factor for a series RLC circuit containip)6s. 3tg:31e6nrh vv k ugruung a 50-W resistor, a 10-mF capacitor, and a 0.45-H inductor, when connected to a 60-Hz powh63vv61et:)ururpg n ku3. sger supply?

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139#
 
单选题 ( 1.0 分) 切至整卷模式 搜藏此题  
  What is the resonant frequency of a 1.0-mF capacitor anv w3pcb rp*4 *d m2wlc,rc qd(+kn1xs4d a 15-mH coil in series?lnx3vspp*q(d ,mc2 1w4*rcbw ckrd+ 4

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140#
 
单选题 ( 1.0 分) 切至整卷模式 搜藏此题  
  What inductance is needed in series with a 4.7-mF capa/,+j5 gipopuor0ol*;fz li v) t(b8fkr)ts j;citor for a resonant frequency of 1p) 0jglo;58izoriks ,jt) ;*tofur/+ pb lv( f0 kHz?

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141#
 
单选题 ( 1.0 分) 切至整卷模式 搜藏此题  
  What capacitance is needed in seriekdkpj+t* 7cy98ayj q(ac x9:ps with a 3.7-mH inductor for a resonant frequency of 1009c8*d x(9 j7y+tcp aqayj kpk:0 Hz?

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142#
 
单选题 ( 1.0 分) 切至整卷模式 搜藏此题  
  What size capacitor must be placed in series xtifhg 83w3(lwith a 30-W resistor and a 40-mH coil if the resonant frequf3hxgi (8t3l wency of the circuit is to be 1000 Hz?

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