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

 作者: physics   总分: 142分  得分: _____________

答题人: 游客未登录  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 magnetic flux 1if*p8e u mnc1except

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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 states tg)e u7 e)8v9h/vmxufghat 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 ofi u/1j ;ka9g2wd rqz(h loops of wire in a coil produces what kind of change on the igq 2wk;(j had/zu19 rinduced $emf$, 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 ma8 g,sk,zdo)kl gnetic field through a loop of wire produces what kind ofso g8d)klzk,, 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 75 c yzw)pe0kpt8:rjw of wire produces what kind of change on the induced k pjp8y cr0 7ew5:twz)$emf$, 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 +13o c )feav ,/ 6oqdvxnw5olyfrom a magnetic 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 anlievd7:hb,1npqf*sc k (5 nq 4 induced current in a conductor will be that which q 7vkbif,nl1:p45he (*d qncs tends to produce which of the following 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 tab5jw)nq:5d qjit/v q4sle. A bar magnet is held above its center with its n 4sdi)5:qj vwq5tnqj/ orth pole pointing down. The stationary magnet 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 horib7hvn ; z:vq r8wwhvmyt0b )2,zontal table. A bar magnet is held above its cennv bq)rtvw 2b;, wh8zm h:07yvter with its north pole pointing down, and released. As it approaches the coil, the falling magnet induces (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 magnm)4-gs 6q8 wuixnos7k dyih1*etic field vector points straight up. The magnetic field vanishes suddenly. When vie 4k*-h)6s wxidsiugq8y 7mon1wed 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 mqnyt ycg+9+ p5agnetic field vector points straight up. The magnetic field suddenly grows stronger. When viewed from above, what is the direction of the induced current in this coil as thp tng5 qy+cy9+e 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 ti.: /-bngbfst. 5zazuhe magnetic field points straight down. The magnetic field disappear.:t5/ afnzu isz. gb-bs suddenly. 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 carries an ever-incre s:7a: fzg:jzd6lnf (tasing c:gsfljf::6t d(a7z znurrent northward. Two coils of wire 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 thv21q0p +*4rv/oso kjkzn xn(he north pole entering first. As the north pole entx 4v *(o+z2kj oq /1nrknvpsh0ers the wire, the induced 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 rota4kv75d8e0p.xj8scgt obn b,bted at constant angular 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 o .7vb 50sn 8x4edbtj,ckgbp 8the loop's 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 angular speed about axmv)vb1mranrd 0976 nn axis whose direction can be varied. In a region where a uniform magnetic field points straight down, what must be the orientation of the loop's axis of rotatio6107r x9m nvvrb)nmd an 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.l qm*cw(b 59co
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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 that a8hbai 4f.r i9 gpdrw):n $emf$ 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 a magnetic field. .1+f7 4ftksdyt hwv;dk hv-l9 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 g1; vm(0ape..ka ysv w/r3q1 6yjchsi in the east-west direction) is moved northward at constant velocity gvjwq. 3 1.r/vey0 ssap mhi1(y6;cka 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 a consae 0a:lo9f(v uf0o)fhtant 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 transabj ,ko*5dv 1x k;+uksdmf-;hforms

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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 -:n6yk;vz w w adzy1vlq0z81z each second. The frequency of twz11n kwl0dza-86y:q zvv zy; he $emf$ 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 device z;1hgmn:;r bz 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 devic z62 rielfr9;me that

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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 sixrw y/cg vka*3b rb)vav.505+-y hvsecondary coil contains more loops than the primary coil thr v.+avv0c -a /hxi 5yrbvk)byg*3s5 wen 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 mov/s inwk.i*lb/ hqbh:a2ln3di *0v2z re loops than the secondary coil then itlh vwnlb/vi 2ibni.*q 3zk* ads/:h20 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 power inpund5h xo:b;2-ui sbq*mt

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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 dmzx z8w ,v6c94tz9j *uo8gzpcircuit,

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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 induct,n4 q,- yoeijbor are connected in series to an ideal battery of constant terminal voltage. At the moment contact is made with the battery, the voltage acrj ,n -qoie,4byoss 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 connecqhmo (h3h-nc26h( ipo ted in series to an ideal battery of constant terminal voltage. At the moment contact is made with the battoh( -(h3n 26ih ohmpcqery, 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 w07xgm;g(v voqith inductance L and resistance 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 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 resistance R is connected to an5t emp )q:z6nf $emf$. 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 battery./:9opo2yuon5lrm z7e0 oym; r The time constant for the circuit represents095eo ;pzl7oy ru2m /no: mory the time required for the current 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 induqufdrjy ce5gky*3(o2* 7hv, ector are connected in series to a battery. The battery is suddenly removed from the circuit. The time constant for of the circuit represents the ticdu23r *(f7 , *v5gjehyqkoyeme required for the current 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 the same units e*.z1qv z ksuu gjtug:z72*l g,xcept:

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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.vvl/h8fiqb0w9*g-f z On this circuit, 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 AC power supply. In this circh5lb j8ck4(lycx/3q n uit, the currentll4 3n (hcx5kbqj/8yc

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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 changeybbqr j99z q bim/w+cz6)-y*cs by what factor when the frequency is tripledy9b+-z)9qycwc 6miqbj z* br /?

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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 acrosk zd8rczx7((j)0 k ;fbszh* eds an inductor is doubled, the inductive reactance of that isj f 8k)0(x;czd( hz*kdrz7benductor

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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 the AC voltage across an inj cn7/pmi eob1)0o4ux ductor approaches zero, the inductive reactano/obxi )p4cm1 70enuj ce 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 saxw ,,j ivc265jxow:nupply. In this circuit, the curre6ca5x ,j xonjiw ,wv:2nt

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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 factor whau1brz4r r 9c/w-ad/hen the frequency is tripledhrd 4zr-/ua/c bra1w9 ?

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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 the AC voltage across a capacitor approaches zero, thefc1lwf anz6 bddn6 58o0)7oge capacitive reactancew571)066 alfnc g8bdzed ofno of 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 voltages of the inductor a5cuhwmndo115tohed 0:odd9ve6r+t 3+r vu d2nd capacitor in a RLC series circuhc1tun+wo+905 md35 1rodorv h62:d tedv ed uit?

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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 da+)lb.c5t:2xh ju7o qi 6u guRLC circuit is defined 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 th s:o6dep;ka ffnc-8w 3x)cqo1 e circuit increases if R increases. When is thi)6pf-efc c o1 3os8akw;d :xnqs 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 the g5 +: h, mmaxzolp7sk(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 circuit. The impedance of the circuit increases gze:a9(fyc0-l kao/ bif $X_C$ 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 z/okdo*d,gry wn;+*k8elb z (series circuit, the resonant frequency of that circuit r;o(gdlkn e*ow bd8kyz, z +/*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 thaf +c2rg*xqkp6 orct73 t is driven by an AC 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 series RLC circuit occurs whene lbj*zb7b51yj8 ck*v

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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 0.10 ma l.8f(+s*cznac izt9 is rotating in a uniform magnetic field of 0.20 T. Find the magnetic flux through the loos. n*f+ ac9lac(zit 8zp 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 a un bxufm:u wr.*;iform magnetic field of 0.20 T. Find the magnetic flux through the loop when the plane of the loop and the magneticrwu *xbm:.uf; 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 a uniform maykbg3f +m49 1-njh eatgnetic field of 0.20 T. Find the magnetic flux through the loop when the plane of the loop and the magnetic field vecto fjg9+-h y atenbk34m1r are at an 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 adjustable single loop+rb5g* zv5sy-l,/a rmqflo4h 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 chan *;mnn,z:a u 2cynqz.qges 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 of wire on a square frame with sides 18 cmrh164zt p8 ,m)mwkrmp . A uniform magnetic field is applied perpendicular to the planhpr84wk )6mrzmt, p1m e 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 tur/ia. vg/ o 8otm.igq.xlj ab,-7w j,wkns and an area 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 andgnyekrbyk7 x17l s9( ) area $0.20 \; m^{2}$ 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 flies horizontally at a location wkcyh 2 /al 4cb(od5zc0here the downward component of the Eazyb/0 k 2 oc5cl(dch4arth's magnetic 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 -xch2khb1;p9c -w pt/n 4qc+ wwfs ,mr;pdw+eangular velocity of 2.0 rad/s about a vertical acqcf- x9w m2 +hwckpw+r,-esp1 dt;;p 4hnwb/xis through one of its ends while in a constant 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 st ;b+x4zcjre ;:9kdm50 loops and a cross-sectional area 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 turns of wire of ar t)--ch dgtv4sea $0.090 \; m^{2}$ 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 80 rectangular lo+pdb / g 9z2yw17h vn2;esnufjops 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 longw n+u yhfe;djngb79 v1s2pz2/ side. If the loop rotates in a uniform magnetic field of 0.30 T, which 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 5 z/lfgq6hv;yp3:soqof 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 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 anjts/sq8md j6v 4ril: : output of 12 V maximum when rotated at 60 Hz. A magnetic field od 4qr/vs6: im8:jls jtf 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 generaty:v iez;(o001uei jywvhdmiqsu tk2: : 0 4od3or 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. The motor operates .f apj+)dza) qq)dcu-u)/rxp 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 resistance of 6.00 W. The motor op .wdd hfg)zau.o,- ,nyerates on 120 V AC, and when running at fulgdan)f zw,h,u.dy- . ol speed it generates 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 resistance 6.0 W is connected tonv5i62*d9 rsb up5lzh a 24-V power supply. The operating current is 1.0 A. What is the start-up curresv b5i29hd5 ul6r n*zpnt?

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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-Vqo:xe6 tung kjzpotjf)8n / y3 b2*:.z power supply. The operating curreynb6gj:f zt t: 2ej./ oon uzqp8*k3x)nt is 1.0 A at full speed. What 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-asdj o)o/. l-zV power supply. The operating current is 1.l zjs)d./oa-o 0 A at full speed. What is the back $emf$ 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 is needed to reduce a primary voltage :wqkpn /e (dy b-5;y 4twtob5wof $120 \; V$ 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 A to flow in tb4bk 3 5 tmu4))ejfvcphe secondary. How mm3tj bef)u4pkvb 4)5c any turns are in the secondary?

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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 necessv6ns23c ew g;x6a7 v6((22)ind h unmum gmrzyary in a 110-V primary if the 24-V secondary has eh()6(mvan2vyug2g;i6 ncw7uz 23m ms6drnx 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 coil anr31o eo 7smj6zd a 2000-turn secondary coil. If the current in the secondary is 3.0 A, what is the current in tho7z6ms3e roj1 e 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 transformeyknql*l,l2(: c v8nq fr. Assuming 100% efficiency, how many amp2 ,ynl cqnllq8 k*f(:vs at 24 V can flow in the secondary?

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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 7 1-l0 yau luo9,anw-cp500 V at 10.0 mA. The pr 0 ,ay-pa91olu-w nculimary coil operates on 120 V. What does the primary 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 uou8b(qtw -n wo8.d :t x20zmsits primary coil and 300 turns on its secondary coil. If 120 V at 2.0 A is applied uqux(s bw 88odt-m2t.zn:w0o 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 p: cl im3tinu)py4yc(( rimary coil and 300 turns on its secondary coil.cimtc ni)y y3 (p4(:ul If 120 V at 2.0 A 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 turpd q.r0smzb ,8tx4mh0ns. If the input current at the primary is 100 A, we can expect the 8 .d0x qb, msmrzpt4h0output 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 haspy/* ,;hft(8p2 iguqh vcz jb+ 100 turns and its secondary has 200 turns. If the input voltage to the primary is 100 V, we can expect the output voltage of the secondary to beq;uph8ytzh,g j( bi +f2cpv/*

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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 has 10fut wi8if4h1x v9 8 1e-9xulto0 turns and its secondary has 200 turns. If the power input to the primary is 100 W, we can expect the power output of the secondary to be (neglecting frihuv1itwxf4lfe -9 utxio1 9 88ctional 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 o)(gvpty:tw w;f current at 120 V. The voltage is usually stepped up to 4500 V by a transformer and trag tp:)vww t;(ynsmitted 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 produces 60 A of current at 120 V. The voltage is usually g;p rd- qwjbg)5.1ksnujn +h, stepped up to 4500 V by a transformer and transmitted through a power line of total resistance 1.0 W.1n- n;h,wugpkrg sb5.)jq+jd 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 current at 12ajbbh th3+a :*0 V. The voltage is usually stepped up to 4500 V by a transformer and transmitted haa j+bh3:bt* through a power line of total resistance 1.0 W. Find the percentage power 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. A ge 9gv/pc/jx u:wwkq x,-nerator 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 of 100:1. What percentage, -wj wx pg9ku//cvq:x 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 h s55rxgi/i9 wyij i5i5as 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 turns ratio of 100:1. What percentage of the original energy is lost when the transwysg55i5x /9ii5riij former 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. How3n jftf42ahd8 z5 yuq: much less power would be lost if the power w y5qj3ffa28z: utnhd 4ere transmitted at 3000 V instead of 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 A. It is to be transmitted on a lirtu paij , 5n;2p.3 uk1jg6cwzne wi jjpa5ik;.tpng3 6,uz1c2ruw th resistance of 0.60 W. To what voltage must the generator output be 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 en*ehc 3(p55 5 tlhgjnugergy is stored in the coil's magne jgp3h(* h5g tlen5u5ctic 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 1m378, *xamn,/xhae 7lvu lkaj8-H inductor. What is this circuit,a/m* v 8l,x3l7ajkehanx7m u's time constant?

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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 wherwr-)4r - tffere the rms 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 +t;.nfip;mzl into a 120-V AC outlet. What is the peak current?

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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. W:4t nt twhb-0anjl: *7:kq2xz jm0hxthat is the resistance of the lamptkxn*-n xqj0 hj0t z4:2wmath: :bt 7l?

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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 connectswey22v edl4 u o8x(/2ca(wlded to a 120-V ac power supply. What is the peak current through the resist2lxe w(8dw/4dcayvsl2eou(2 or?

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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 connec d;pwkgyxg x42y6 yu.8ted to a 120-V ac power supply. What is the power dissipate 4p2k6yxgxd8ygy .u w;d in the 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 50-W re:kxa+ack,v(/hzs / hv1 *nxvx sistor 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 50-W resistor isk(1l gprso-*u $I = 0.80 \sin (240 t)$. 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 50-W resistay f3)59xj0zynne6ry or 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 reactanced6bc/ai c. r-q of a 1.0-mH inductor 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 (9/y/pt obw,s8nbgcn of a 2.50-mH 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 coil have 14.0ohit3uwr,: ztaf-. pb8kc9p 1 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 oohl,ar0/g2 )v fyn ui2vjn: )nf inductive reactance at 1000 Hz?

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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 9.c hstyc y;2 g+f3ueha 60-mH inductor when 120 V AC at a frequency of 20 kHz is applied ty cu9ehty c+gs; .2h3fo 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 througjq7v ws2ljz ;/h a 2.50-mH coil due to a 110-V, 60.0 Hz source?

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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 reactancg qua:)t 69ucbe of a 4.7-mF 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;gg+f0 /smcci capacitive reactance 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 does a 10-mF capt7f f-d+ l7/ 4bplcdraacitor 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 reactance of a 0.hv7xgpo w u k673zo7g3010-mF capacitor be 100 W?g h6poo7w 33g7ukvzx7

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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 capacitor at 10:w5tbmpbu( h n-k2o y2 r8u,aq00 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 circi w5z+j (lspf4uit with 12.0 W resistance, 15.0 W inductive reactance, and 10.0 W capacitive rlw ifzp4j(5s+eactance?

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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 c; zw5: +dndcwdoil, and 1.0-mF capaci +dw :dzdc;5wntor are connected in series?

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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.v,xeiui + b-bz qyr ,/7cj)a9j0-mF capacitor are connected in9uj7rbi- b ie,aqvj+xzy)/ c, series?

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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 con6xda0o h7big k,tk8 :gnected in series with a 20-mH inductor, what is the impedance at 1008 ,bk:td0i h og7xg6ka0 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,4jf phzokyjjd 6g10iu bt **aq3):od a 20-mH inductor, what is the p, thau0okzyqj j6db :*ipfdo1g4)* 3j hase 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 circurjd:f-) p6o/agx 9c vwit with a 20-mH coil and 1.0-mF capacitor p)x6/ rd9aofjc :g -vwfor a total impedance of 100 W at 1500 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 with a 100-W rebg94rl p :2:e0rczjcasistor and 15-mH coile24 g :cp0zcra9j:lrb to get a total impedance of 110 W at 2000 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 seruw (vm.nq 6f4myi htv7/q*ar6 ies with a 450-mH inductor at 5000 Hz for a total impedance of 46 (/4q fqtw*r6nummyiva v .h70000 W?

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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 sbgx:n0tr86vh0+h w1 i z,wrkceries with a 100-kW resistor at 1.0-MHz for a total impedance of 15rwnrzg+ 8 txkbvh,0i:1wc 6h00 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 seriez0s hvy 6177zf + hqcpai6h7ses with a 20-mF capacitor. What is the impedance at s 6hsizhy zq 1pf077e6 +ahv7c1000 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 a 10-mF casv(fo+;/f *fzio*1fv tyq k:cpacitor at 1.0 kHz for a total impedance of *o/+:f v1 yksofz;*tfi qfc( v45 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 needed in series with a 10-mF capacitor at 1.0 -bk n*7gpz4kjkHz for a phase ang4pg* j-n7zkk ble 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 in series with a 30-W resg8ln ;ik y2zs7p91 ci4p -vgveistor at 1.0 kHz for a total impedance of v i79gs -c1y;ekzg vp2l8nip445 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- k0;rqfqgkq 2x yvkxe9-*ljtc-+* dr,mF capacitor at 120 Hz. What is the phase a*f-grx jte;kx kc-9dqqvl+0 k *y2q,rngle?

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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 pxg4tgx;5st4, and 1.0-mF capacitor are connected gtt 5gs44xp;xin series?

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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 capacitor, and a wa:v;: 1oz0cc j hy7bz0.350-H inductor. The circuit is connected to a 120-V, 6a70 1: ;wbccv zhy:ozj0-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 capacitor of cc :ai kk(xdtz(uhv/z: z*ykk 1*18z yaapacitive 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:(yk ticykvz1 h k z: */a8auz*kdx1z( flows in this circuit?

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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 circuit containge8)sc a2b5 iling a 50-W resistor, a 10-mF capacitor, and a 0.45-H inductor, wh)52aebc i 8sglen connected to a 60-Hz power supply?

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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 resistor for a phwxs -1p1x k8bh/.hz +p:cszhr u+gm(vase angle ofz.: (zvp x+1h-sxb/g+pshkh rmu 8 c1w $40^{\circ}$ 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-mH, C = 10.0 mF. ov 1+ *(rb0cf emkhsn5 At what frequency should the circuit be driven in order to have maximum powek on+ f0 shm(bcev*15rr transferred from the driving source?

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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 resista7u1ng*1ia k0jf 0vmha0hrt8z i pf c/;nce, 15.0 W inductive reactance, and 10.0 W capacitive reactance, when the nfc 08tpf10r ig h*vj;0/hza mki7ua1circuit is connected 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 AC circuit 1v) 1plxyv0kois $63^{\circ}$. 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 1rb/an ej 6x(sxnth:3impedance of 60 W and a resistance of 30 W. What is the power fac:3hnxn61s/(bj aerxt tor?

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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 containinebfz9 bkdpugs38) (3fg a 50-W resistor, a 10-mF capacitor, and a 0.45-H inductor, when cfkd() bgpeu3b8sf9 z3onnected to a 60-Hz power 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 frequen3-p+bgf: wvej cy of a 1.0-mF capacitor and a 15-mH coil in series?:b-3e+ jw gvfp

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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 capacitor for a resonant fre8hrsve fn9-69tyrz ,1xtrj9y2 :k )pbcrq( jzqut)b61yvzpx r9qr92rtk f:yeh,(cjns-jz8 r9 ency of 10 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 series with a 3.7-mH inductor for a resonant f:iuk.x(3 fh gngbak d7-5yt t)requency:5kty7 )gd khgx.fu i(nab3-t of 1000 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*o vcn(7q e; htl/q-yt be placed in series with a 30-W resistor and a 40-mH coil if the resonant frevq th(* 7yl;/e ncq-toquency of the circuit is to be 1000 Hz?

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总分:142分 及格:85.2分 时间:不限时
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