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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 magn72m )fo/xba9;vezo yi etic 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 states that tfoe, x;nl * :m*/hj7ocfge(llyu(z 9qhe $emf$ 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 loops2z5f -auopeyd .n,t, gpy-;si of wire in a coil produces what kind of change on the i,pns a2uy5pto -dye .;i-g,f znduced $emf$, 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)mrz8uq (br+g91 kqz+ 1tjjkd the magnetic field through a loop of wire produces what kind of 18 qr)q+b1zd uzk j+t9r gmk(jchange 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 produces what kind of change on the indehlsne ,:o(e6i pn(4qucep( osl n, hee(6:4neqid $emf$, 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 ftu70yz-5 p 0jyh c)mtjrom 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 an ivss2c) tywyq 6v28zs )vt6qn7 nduced current in a conductor will be that which tends to producw68ts q 26)v2tyyzncs sq 7vv)e 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 table. A1rpx. )1zwb kp bar magnet is held above its center with its north pole pointing dowx.bpr )wzkp1 1n. 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 horiyy ba)8baww+, zontal table. A bar magnet is held above its center with its north pole pointing down, and re+wya yw8 )b,ableased. 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 regiml6jq* *an,i won where the magnetic field vector points straight up. Theil 6mjq, n*w*a magnetic 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 udm/m(qt/ *0wgtyyq : table top in a region where the magnetic field vector points straight up. The magnetic fuqty (t0yw:m // *qdgmield suddenly grows stronger. When viewed from above, what is the direction of 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 whe p pmyox8p8jd*a: f, (re*dh1lre the magnetic field points straight down. The magnetic field disappears suddenly. Whe(da,efj* d8r 1pmxlo:8y *php n 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 anzo zyifv4o8 19+u pe8uh l9-wjd carries an ever-increasing current northward. Two coils of wire lie flat on the table, one on either side of tiv-y9 hoz 4lp81+ 9ujzo8eufw he 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 nog4m9*,puc (y gvvp5f:w4 hwvgrth pole entering first. As the north pole enters the wirfwpc gv yv 4w*4:9umhgv 5,gp(e, 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 rotated at constant angular speed acms+ks1 v ,8cvbout an axis whose directivs8vsc 1c k,+mon 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 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 abdr(x7d:lca :pzc, jhs1f;8 qdout 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 loop's axis of rotation if the induc 1q f:xp;cc ,d:87dr(lhajdszed $emf$ 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.94yaw, z ld 4nnvt*7wa
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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 an z2 t3jl9y(ud 3 n6gzv u;)ooih$emf$ 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 magneticrw-/pe /vc h;c 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 (orie,j-al9 tnc4o gnted in the east-west direction) is moved northward at constant velocity through a magnetic field that points straight down. Make a statement concerning the potential induceg4aj n-, l9octd 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 constant angulavl,.+bhux 1s6tvxmur9 -yqm 2 r 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 transforq lu dt09jie;ys /3fq1ms

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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 revolugvk(f obg+ oktmui;z+,lu .)i-7/q xetions each second. The frequency of the mo, gtoib+.k7zkg uxl)+;i(v/uf-qe $emf$ 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 us ,08r ky0- 7ybdcddl nb sbr8d.j0tpe5ed 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 devi(r (frt. 3kq d5xvvvge6a8tl -ce 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 secondary coil contains 35hb3xu9j bccn5 jvp 1more loops than the primary coil then it is a195vjcb5cn3b3px uj h

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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 more loops than u wpbqj keh l4e)w(-d9,c*x5.qljp/a the secondary coil then it iqxd5jk4 qlww cpl,(j -h/apbe.u*)9es 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 2(wq it3cd71t::j 7y anlky q:t z1i-ryata5binput

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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 resonantq .4vm oddyjr.*6yqi9 circuit,

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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 inductor are connected in series tca)p 5)o/k akco an ideal battery of constant cp5oka/)ack ) 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 conneu5yw2,e7( sguu fhnv-cted in series to an ideal battery of constant terminal voltage. At the moment contact is made with the battery, t2s(w5uyh7u,v egf-nu he 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 c(ec ;2z )bs8lequp) sedb3 :q.8y. vdbgqyb (oonnected 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 tg rt;*g8 aqkm/ uj35nqo 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 batter raysn,1/ .gegyv:c0smx;7 h5qjs1fxy. The time constant for th/fg5r;v js me0y yc11xqn7sa s,.g:xhe circuit represents 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 inductor are connected in series to a batt3n)uh(ml3asw x -mby3p;0 rkoery. The battery is sudden3a yx ums o0rh;lm)k3bw-n(3ply removed from the circuit. The time constant for of the circuit represents the time 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 u:8 6ncm dn(((her2oa j-pvsqanits 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 supckqex9 7u1na(-vd ,dn ply. 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 cir)o7qh39;mksj .2 tuzij pvy 0fcuit, the curren0hj2 y k93qjzs.m)p i7uvt;oft

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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 ch6qa dsy; 4xu8nys7eb6x/m yp)anges by what factor when the frequency ;xbp 78n) s6/ydy ymse4x6uaq is 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 inductor is doubled, the inductin49( d(coz*f -gvch9 pvhwup5ve reactanpcnv *cpo vwhf(g(dh5-99z4uce of that inductor

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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 inductor approacmxji vglo -i- c7;w,q0hes zero, the inductive reactance of th ji - i0xqo-cgmlvw7;,at 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 circb6j1q8kkverb8dh t);z zf82rvf h +f :uit, the current1vk6 efzd8k28bz vfr:jf +rb h)h ;8tq

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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 char) w:8i ;ykrsf es4sw6nges by what factor when the frequency is i6s s fe;rswwy :48k)rtripled?

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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 approaz5v zdv8/ak, ( 2abbrrches zero, the capacira8/5z(2brbv ,dk zv ative reactance 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 betwsvo+ahih5g)yb k 9, 0aeen the voltages of the inductor and capacitor in a RLC series circovs9),h+b g i5aah ky0uit?

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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 def fzm,v ee+ahwyiz, pv;n5 /9f1ined 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 circuit increases if R increaseva q,qr3s ec a 6a(;4lh1dhf3e b/hf/hs. When is ,6d3fsl v(qa ehh/h cr /;efaah q431bthis 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 9,xdfcrd,hz *ip i25jthe 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 cg1zejj-2 nv;c ircuit. 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 cap a4k)uys+q.nm 27tkr aacitance both double in an LRC series circuit, the resonant frequency of that circuit wi.y4srktuq+ 2an ) ma7kll

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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 AC appry3qf, uh0kg-vs2 ,culied 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 whet ;9 ntvl;0gyen

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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 m is rotating in a uniform magnetic fi/m 0lo g yw;)t*0klybqwmb-6 reld of 0.20 T. Find the magnmo*ry-q;t lkblg/ybw0 m 60w)etic 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 a uniform magnetic field of a,oii 7 rawkk4wz:yaza2*:c(0.20 T. Find the magnetic flux through the loop when the plane of the loop and the magnetic field vector are perpendicul7 a2k4ai,:woaizkw *c:a r( zyar.

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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 magneti*sjq pv9jwr9h;oy, 6/067pq q lyakc bc 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 an y9ahcbj o j/q6*spvy ,qkqw;7pl690rangle 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 afz+l0 yf9a ty5n adjustable 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 31wnd+ih q:a2b2bzzy25o h fvq0l2 vechanges 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 abtdc 6l5l 851hf9yn1o 3 yj+y1hljoa l square frame with sides 18 cm. A uniform magnetic field is applied pe9cyll5h+ lo1fo 1tbd 8 3jy1h l6jy5narpendicular to the 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 j um tbd h8/4j5i39booan 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 and areqn,3y i9wb8zr a $0.20 \; m^{2}$ 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 horiz8o, ddt2 dd.fa 6zi7cqontally at a location where the downward comdqo,8d 2tifazcd.67 d ponent of the Earth'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 angultv8dyqw :)jx9-caqw pm15 o ozl97b x,ar velocity of 2.0 rad/s abou9,t 589 7mw-x :cvwj oybpaz xd)1qoqlt a vertical axis 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 50 loops and a cpd4h tug9sf :pv+pb 11ross-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.bztgn/stb :- vc)x5 m 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 80 rectangular loops on its armature. 5wsw,z,jnnu)z i0h k -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, which is perpendicular tosjh- ku n win,wz,z50) 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 wire of arejyb2ha1b* m.d7dt.lmf5dv k c18 5waea $0.090 \; m^{2}$ 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 generrs7n bl5srcuri3k;w 95d 1r0 oator with an output of 12 V maximum when rotated at 60 Hz. A magnetic field 0 us1rnsiw5lbk d ro3 ;rr5c79of 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 generator with a maxim pj i,*i;4 plsdcg1aujxu)c-+um $emf$ 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 op +wksdhjz ,pj: ht(.jfzlj/*0erates 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 operatm/1n e(.s f)67elzumtcuj j) kes on 1l /mu(1fmne.7 ut6kz)jcj e)s 20 V AC, and when running at full 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 to a 24-V power suppxf7* q -4bpfzmrbik+2ly. The operating current is 1.0 A. What is the start-upz- ifb*+m7qb2 r4pxk f 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 power supply. Th gid*:w 8nzi/ w9v7cdie operating currd:wni9wcvg / i8zd7*ient 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 resistancd+br wp+* vqj+e 6.0 W is connected to a 24-V power supply. The operating current is 1.0 A at full speed. Wvbj+p+r* dwq+ hat 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 of /*xr kv(jc bf0 ;6ycud$120 \; V$ 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 os lzuaa(+ 54*q.gymgb (f9rm xh8c(q ef a transformer causes 14 A to flow in the secondary. How many turns are in thzqml .(hf9(baqs mc(+ray u*g x84g 5ee 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 necessary in a 110-V primary if the 24qrx4tb(nf/ 8-0jpiark2 kmu. -V secondary has 100 turubp4k8r2.t- a 0 k(qn fxi/rmjns?

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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 c(+ 6ncv93yf tyx5dlfprimary coil and a 2000-turn secondary coil. If the current in the secondary+x v l96cny5ydctf3f( 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 nc7 8aty 1h*c ,5u;6cibo)lbxw6 cdcwtransformer. Assuming 100% efficiency, how many amps at 24 V can flow in the secondaryw uo6tnh,;cxily w )cc8bb5 1cd*7a6 c?

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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 75 fbw:tkm e +gc7zl(*aow;/xr -00 V at 10.0 mA. The primary coil operates on 120 V. What does the km*e+otal:(-r wf z bcgw;/x7primary 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 primary coi5lk t 8g.ccxia7qjg52l and 300 turns on its secondary coil. If 120 V at 2.0 A is kjcq52a. l85tigc7x gapplied 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 and 300 turns on its sec kb7xvm+nxvjfbb. .45ondary coif5v.+x7 . nxb bbkm4vjl. 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 tzjlm1s.s9+v2v rsx.fy94 uyaje: v d0 urns. If the input current at the primary is 100 A, we can expect the output current at the se.1mje24 vxzl ss9 usyvy:0.9jd+afrv condary 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 seconda3j-ywvamw e f)nb2z)-2v d 0nzry has 200 turns. If the input voltage to the primary is 100 V, we can expdy)f3z 0 wvv -n22-bmjze a)wnect 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 has 100 turns and its secondary has 200 turnstq0xhs91f yya9h o/m6. If the power input to the primary is 100 W, we can expect the power output of the secondary to be (neglecting frictional0fa6qxh /9ho 9mtsy1y 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 current at 120 V. jlz(crplcy. x27 t1m( 84fvgc 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 number of turns in the secondary pl.2 z1 (7xrtg y4(vmccf clj8if 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 c :cf77qnl 3-riuz.bsburrent at 120 V. The voltage is usually stepped up to 4500 V z. rbn-f s3liq7u7:cbby a transformer and transmitted through a power line of total resistance 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 currd fl,4t.jrx+ 5 yknq1eent at 120 V. The voltage is usually stepped up to 4500 V by a transformer and transmitted through a power line of total resistance 1e.1qfkj,+d lt n r4x5y.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 gyjtu3gtzr y-z8 2k.r+v;8wg 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 tgt-ry; y zz3wgg k.jv28ru+t 8ransformer with a turns ratio of 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 lgd( -y alvje htx0w16(ine 50 km long has a total resistance of 0.60 W. A generator produces 100 V at 70 A. (gyl0 vxjw-6(d1eht 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 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-Wn rb ionj3q-3- line at 1000 V. How much less power would be lost if the power were transmiqib- 3 3-jnonrtted 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 l3 +w+4jnjfddp3zfw ,nine with resistance of 0.60 W. To wn,f n33j4+ dw z+wpfjdhat 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 energy is stiemqj9 ygciv8 rb1;:0 ored in the coil's mmvjbgy :i;q8 i er91c0agnetic 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 contab+5 qz :;rxggp2iax+xins a 6.0-W resistor and an 18-H inductor. What is this circuit's time consta i:p;g2b g+axrxx q+5znt?

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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 w1z*; nin( dehxhere 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 into a 120-V AC outlet. Whatxj) n mzi+3r,q:hfd0r 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. What is ri)0c-+9c ,ntmshiuq6z z as*the resistance of the la zs) ,qt* uin+mcha9zir-cs 60mp?

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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 a 120u,hlp-z4bh1q0jt c( b+ lg0ae-V ac power supply. What is the peak current through the rp+ c4tlb(he1 h gzqbu,l00-ajesistor?

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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. What is the power dissu2,rqava6r n h,;u3lkl. +folvn7 ,ji ipated l rqhvniako.,,3 aufvl,ulr62; nj+7 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-;4 jq1) yzz;wu,hieadW 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 50-W resist wpgbs mg8z805ry(r 8por 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 50-W resisto /ypzbxnm .zo3qm3*0lr 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 induct ckswyw:jz7e,. )ul:rt,af r5 lj (b4tor 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-mH ;+m hvoa9 h +z.k9lmrncoil 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 havd7 77g mmy+non2r+np b 10lcske 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 fosr.-.8;stdzusw3ej h r 157 W of 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 a 60-mH inductor when 120 V AC ra0aymz .c/;*t 8 xmeqat a frequency of 20 kHz is ; rc*8.ymaazxe/m qt 0applied to 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 s8um 8ejczm( 5f 0anv gtr(/o:iource?

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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 ov oxjn-+:dz-pju0pyo *7ifp4t0-sl qf 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 iso8 zoy, zub2 .9 cl/hyitduz6- needed to have 50 W of 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 capacitor ;amk:mp c;m h+4;l oecs /nkve,3ls7hhave 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 wilu x )h0 nz.(ddwjh61vijr (bc.l the capacitive reactance of a 0.010-mF capacitor be 100 W.jhrwdjhcuxbn .(i ( 6v0d1) z?

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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 1000 Hz and 5.0 a9 ry6e4)ao wn4wdx4hV?

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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 circuit ctkxl2(b0l a02+ 6 kax*l rlwrwith 12.0 W resistance, 15.0 W inductive reactance, and 10.0 W capacitiaxl k(2bcl+wlt*0 arxr6 0kl2ve reactance?

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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 tqpkcca7fmf 9y4h kt0t.l6:*coil, and 1.0-mF capaccham t:6tyf79p fcq* 4kl t.k0itor 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 1500w u303eriuxvoe:7aa4 5o(;nm x8f rwj Hz if a 100-W resistor, 20-mH coil, and 1.0-mF capace5e7 rno8: o4iau3 ( jw wa3u;xv0fxrmitor are connected in 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 connected in series with a 20-mH inductor, what fnbhr/c5(( el.f0c x ais the impedal5c.re abchnf 0/(x(fnce 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 inductor, what is thuiyzm8n7yr6u ;vh0j35xzmzdp w9o q 6nn :i4.e phase angle 8jiuiouny9n d6 zhzy: 3;7 6nmpz rqv4.mw0x5at 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 circuit with a 20-mH coil and 1.0h) yx/ wfk94(oy+drv yuin 35:skml:o-mF capacitor for awvsyoydk k h+:l35nm : )f iu/(oyxr49 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 capacitancesn:c ac ;ks 0p***vyjvs is needed in series with a 100-W resistor and 15-mH coil to get a total impedance of 110 ;njy* skspvc*v:0* a cW 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 iniiewlw 6 /)6u4lrg8t n series with a 450-mH inductor at 5000 Hz for a total impe nwug/ir 8 )w66ll4itedance of 40000 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 series wi428h4r lzmlnp th a 100-kW resistor at 1.0-MHz for a total impedance mrnll82p z44h 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 l26 brtjhmwa4 owgpy,+-n(x,capacitor. What is the impedance at 1000, w-ga 26oj bpyw+mrn4xht (,l 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 needed526lh0j kkgqmfd )8r c in series with a 10-mF capacitor at 1.0 kHz for a total impedagc0r )628m5kjqdkhfl nce 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 needed in series with a 10-mF capac75uj ev.g:tutg- 9sw titor at 1.0 kHz for a phase anggteug:5-7jtu9 . svwtle 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 sy* z nenmk(x *hy/t:fzu,d e6.eries with a 30-W resistor at 1.0 kHz for a totalx6zum/td *(k:z* yhnf. n,y ee 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 capacitos,ro822 4hemu :kgrdfro 5j *cr at 120 Hz. What is the phassg4e5hfjmroc d 2u: *2o,r kr8e angle?

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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 5x 4xjx n()vjz b3(uz;l.0 V and 1500 Hz if a 100-W resistor, 20-mH coil, and 1.0-mF capacitor are connected in se3jvb zl x z(n()xju;4xries?

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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 ynjw:k( f5ump7,0i9rfyo+f yn 2dm;c a 0.350-H inductor. The circuit is connected to a 120-V, 60-Hz power sfk7,(:9owyn r+yj my ;2nc pfmi0f5duupply. 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 capacitive reacveh k/pdp1r/0y 7vq /mtance 30 W, and an inductor of inductive reactae0pvy rk/pm/hq7 /d 1vnce 30 W are connected in series to a 110-V, 60-Hz power source. What current 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 ang n +w+o kzzgd/*b.q/xmle for a series RLC circuit containing a 50-W resistor, a 10-mF capacitor, and a 0.45-H inductor, when connected to a 60-Hz powerd/+ nzb.o+ *mzwx /gkq 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 scyks fh620q8series with a 500-W resistor for a phase angle of s86y 20 kqsfch$40^{\circ}$ 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 = 2 :l.-:bme)fxbh , mliy0.0 W, L = 200-mH, C = 10.0 mF. At what frequency should the circuit be dm:lhb .-:ixyefmbl) ,riven in order to have maximum power 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 .9l 2rpur+chi82s8 v:kvc kxdin an ac series circuit with 12.0 W resistance, 15.0 W inductive reactance, hcr k+v u82: k8lpcrx9svdi2.and 10.0 W capacitive reactance, when the circuit 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 ann l43i7;ge1qinj7l z v AC 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 of 60 W and a resistance ol *ad63zcbmx2 f 30 W. What is thbz d23xla 6*cme 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 containing a 50-W resistor, a.2 wdg()z p rrnr-p:w/9t7 a )givldon 10-mF capacitor, and a 0.45-H inductor, when (nog9dlw-z: rna2)v i pt .p/gw )dr7rconnected 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 frequency of a 1.0-mF capacitor and a 15-mH coil ijc.yz*m76y z0 aa z/lg*pc-pin series?lp.6zmy/ya*ajgi7 *0z -cc z p

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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 rx0d8 dqrkri(+ru d+o m*k*l4uesonant frequency*ml+k0x8u qd*ord4(d +rukr i 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 qi edjt ay.4jxr; ,u/y/ys/p(a 3.7-mH inductor for a resonant frequency of 100 ys.(;xjat/yyrup /qd4i, je/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 with a 30-W resistor and z7d(: anqf ,fja 40-mH coil if the resonant f(fz jndaqf,7: requency of the circuit is to be 1000 Hz?

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