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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 mag68 6 mni/pe5/slzsnin netic 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 ind,o + 6ds1zykf uv9d7jb sjt-.ruction states 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 wirniwd4 c9-3 lhodc. )mde in a coil produces what kind of change on the induchwdmic3- do )4c ldn9.ed $emf$, 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 field through a loop of wire produce7bn4ox)v1vd5zf dtu ,g (ymz (s what kind of chanxz4ytd7vn1dm f ,5uoz bg((v) ge 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 in;8b a:mcqvhm7ezy5 l.duced a7q: lzyv8mbmh.5;ec $emf$, 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 magnetic field an ( ceoq2rxa:tqqnf:-t+9 x /h m$emf$ 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 ag5mq /z16 wvbrn induced current in a conductor will be that which tends to produce which of th/5 br 6wzvgm1qe 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 tablul,/*sp ) o,*lq-gvm fseem ajzi0n (.e. A bar magnet is held above its center with its north pme0*mj -g)n ,ql/si o,ufzs e.(plv* aole 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 horizontal table. A bar magnet io9(,uafstjc + dr c9bbb,xew 60i7lz; s held above its center with its no jbe, ;s ouclbx9 7 fi(abrz6c,t0d9w+rth 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 magsyq-:ig * ;2fqiaub 2rnetic field vector points straight up. The magnetic field ;agf 2y b-qir:iq*u2s 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 maghjpge*t3y 22lu hh*75qz4z ch9dya d9netic 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 the field incjphc2 eqt 93h9d*7zzy2 uy 4ha5h* gldreases?

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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 t+k4mkfpakiqlu0 *ew (6c7 ww(op in a region where the magnetic field points straight down. The magnetic field disappears suddenly. Whenqmw6+*w kk4 k7( upeia l0c(wf 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/e5 e1aioa 1gjlcucz4s ho0;0 horizontal table and carries an ever-increasing current northward. Two coils of wire lie flat on the table, one on either side of the wire. When viewed from above, the induced czja s1h/u0 a ;eeco10c5lg 4oiurrent 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 entering firsszevc2ev ,46 jt. As the northev v6se,zj2c4 pole enters 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 rotal):z (xrcbz f2ted at constant angular speed about an axis whose direction can )rzlf(2xb c:zbe 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; -ay.fl /+nog4 blqnb angular speed about an axis whose direction can be varied. In a r4nfb;bno .-g ly l/qa+egion 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 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.m3:w3v9dlxhwg+ws4 4+ ppo 7g u *bkbt
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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 th0xsf ;i5s4 7mxuoo k,vat 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 a magnetic field. The gi o *7.: l(zpr:znxiofj6i5 qri ni-7$emf$ 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 movedq lh;:h riqrapd 6* qo7ius78- northward at constant velocity through a magnetic field that points straight down. Make a statir;*:diq8loqph s-6uh a rq77ement 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 rj/z t (c chm8eap /.)h+icnbk 54pr6znotates at a 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 4o sowjto :0u.transforms

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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 second. The frequency ofrtt ubi z+qw 9j7l11+p the i u7+rb1w lt9q tjz+1p$emf$ 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 used a m+ clckg0)g+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: hpy sogz960fe 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 9h69 (hxelejs t/ ;tp.qgm l3isecondary coil contains more loops than the primary coil thxep/hl.j6( t 3mtlg ;e h9sq9ien 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 ipjh;:n u6,-v:p n,hx uwuhi.coil contains more loops than the secondary coih ,xu;nvj6uhpw h .i-u p:in:,l 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 powhfc42h;zi9e *+b ypnuhyn2o*er 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 ihr:6q8. k;lmxuity,4 y*a. dn 5zdxxcircuit,

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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 to an ideal batt(nwl;)oyv8l 08sl+2 h inugtfery of constant terminal voltago (8n vy t)w8sf+2l igl0;ulhne. 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 serv;f7z xl*nj 9l ypv),dies to an ideal battery of constant terminal voltage. At the moment convlnp dj;vf z) x*,yl97tact is made with the battery, 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 resist-i mlbws,x7l4 ance 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 andj hug0vyr-d49h( /lwd 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 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 aregpvvtf 6(2 zf6 connected in series to a battery. The time constant for g6v6zfp(vt2 fthe 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 ufys 0.zgq*zni2 5fk7 bnx 0ub i48l6xare connected in series to a battery. The battery is suddenly removed from the circuit. The time constant for of the circuit rex0f 2uki0xf i.6*5uyqlbn8b7z nzs 4gpresents 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 unitsi8ujzq i.j9zt4c /cul5; jb i8 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 j6q /mb2vxkv sg9--) bj1cxhx power supply. 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 an9 nx-*of(yzke; ( 9esmmxt2ys AC power supply. In this circuit, the current992xso yt-fm (xek(; mzes*ny

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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 w/tl:egxz 579a ytg9uihat factor when the frequency is triplede l/7: x9zg9t guti5ya?

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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 inductoxqh) j6*v40lypsta) asx82ub r is doubled, the inductive reac l06u bxatsxv)h8 42ja*)pqsy tance 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 approaches zero, the g8 *bgi 3 ljo mn(l42comvd2n1tav)b 1j(q7hp inductive reactance o3 b24v)qagv(7 p12gl8j(o nilcm m1b hojn*dt f 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 circk6 l -n-,iiee,d0qx akuit, the currenki6 ee nad-kxl,,q-0i t

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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 cha 2u *f( bx2reg+e9lgbsnges by what factor when the frequency is tripl2ebs +(x9r uegfbg* 2led?

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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 acrwn 8x5ztc1c+doss a capacitor approaches zero, the capacdn cwt xcz1+58itive 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 between the voltages of m+oklj0x+ z(qj3+j3qe fn az )the inductor and capacitor in a RLC series circuiq)lj+f jaq3o(++3jkxmez z n0t?

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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 atxpq20*j0 on)yvf 0)cja zg 1hn RLC 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 circuit7(sv sy :+pkie. The impedance of the circuit increases if R increases.(i v:kss +ye7p When is 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 the circuitzq/te35clnvy6 ivq /4 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 cir9gy:e7-i4 jspaedixb hj(,m 8 cuit 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 series circuit, the g:xnz yg(-sy 0resonant frequency of that circuit:ygz ( n-0gsxy 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 AC appznli fnz5(q;,lied 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 occu .wjobe62o i)f-i so4jk-y)rjrs 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 0.10 m is rotatin/*f-s+lwdq6 -m lamx6sq :)5in xzzzug in a uniform magnetic field of 0.20 T. Find the magnetic flux through the loop when the plane of the ql/5x* :l-+ zfm 6 nm) daqwzzxsu6-siloop 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 uni8+px(wf/m0z v lm pgo,form magnetic field of 0.20 T. Find the magnetic flu8pl+( mgm 0xf/z,pwo vx through the loop when 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 b8as u/ a, whu1t.bd:qis rotating in a uniform magnetic field of 0.20 T. Fiquwa1t h8/.sbb, aud :nd the magnetic flux through the loop when the plane of the loop and the magnetic field vector 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 adjustablwe**i -1( zbur aniywj c,k06he 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 coilnw/tm4d jg2y tm2i: sxg-7; : 5wvcmtm changes 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 cm. .e :*p9v zqebzltssv5g5z*mkh ol1) , A uniform magnetic field is applied perpendicular to the plane of the coil. If the field changes unifor* skezbp*qhlz) 5e5ls to,v:v zg1.9 mmly 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 t u2k ;gbfz, xsd5l+sb-urns 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 and area4w33r yrz ;jtbizxc:/ $0.20 \; m^{2}$ 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. 8n1gkj3)p ufdaur qj4)c)lo horizontally at a location where the downward component )qdagcj831f jrnpo.u)k )u 4l 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 c .e9+2 g0. flk 6epdmb6cyiodconstant angular velocity of 2.0 rad/s about a vertical axis through one of its ends w0 9cp +m2bfl6k. idd.ego6ecyhile 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 b;h5,w *4v5bv u ht qp fcees7)9ugy3v50 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 1gapq0s8o70e a 00 turns 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 80 rectangular loops on its armature. Eachqr nh( 07f;eclp)*n7no .j a l1wpbrvv1/a/zd 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 to the axis of rotation, what will be the maximum output voltage0p*qz/ afh1rol )7.ven1an wnr7v(j c;pd/lb 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 10yro8l*c ,ex,v ljxr zca1/9w )0 turns 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 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 generaax muo4fyxm8eoc3b z6t.r; 6 4tor with an output of 12 V maximum when rotated at 60 Hz. A magnetic field of 0.050 T is available. If the area of ; r4bx.omt64omcf8ze au3 6yxthe 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 isl(auy ob//4 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 on7oj ui8kwlaw ;5;s+ sk $120 \; V$ 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 ha y gp(ltnm)y51ve a resistance of 6.00 W. The motor operates on 120 V AC, and when running at full sny pmg)ty(51 lpeed 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 tot b ui w)avxns 3s4 a;6pa)lrh6k6a(,h a 24-V power supply. The opera6sapw4(i3l6a;hk)b trsa6 nhvu) x, a ting current is 1.0 A. What is 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 connecteddhp8u b*l2 j;t to a 24-V power supply. The operating cur2pj;tu* ldh8b rent 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 internl+slm 3ic *yd(qs(ynwta1j-1 al resistance 6.0 W is connected to a 24-V power supply. The operating current is 1.0 A at full speed. What is then1 yt(ac3(d* ssj-y wlqil1m + 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 volram)n(wbk 9s7 tage 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 transformed -ijwx4r iy+ 24marr-r causes 14 A to flow in the second + wm4-yirir da4jrx-2ary. How many 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, hox.*hoi,7mzvp+kc; r yix*o h) w many turns are necessary in a 110-V primary if the 24-V secondary hh. *xx,ikh+zry 7 *o;vpmio c)as 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 and a 20zg2k fe.q: wc500-turn secondary coil. If the current in the secondary is 3.0 A, what is the current in the p zgke:q.w5cf 2rimary?

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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 transformer. Assuming 100% effijpw.- ml xe4bg1ol0aup-jfwy 72 ,y9nciency, how many xb 1mwea, 4o7-.pg9wf 0n yjyjllp2u- amps 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 7500 V at 10.0 mA. f2abs+2pl;qp, th2p6fjd3p qpwo2y( The primary tj +;63p2y l2(wb pfpoqd af2hpp2 q,scoil 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 turnshi th:zs;/r;ov m0 2lg prl.a: on its primary coil and 300 turns on its secondary coil. If 120 V at 2;:.0opsgli:at ;hh vr/ lzm2 r.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 i3rwdcz+saom ro8) cvsz;6p n+3p z t-.ts primary coil and 300 turns on its secondary coil. If 12zm snr8do;3t+ c v)p-cwrop63az+ .zs0 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 tranem1/8i ai.s hlsformer has 100 turns and its secondary has 200 turns. If thl18ai s.mi eh/e input current at the primary is 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 secondary ha.7l, b0hf lupps 200 turns. If the inpllp07p, fbu .hut 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 has 100cnyub(0xx q1. turns and its secondary has 200 turns. If the power input to the primary is 100 W, we can expect the p uqy(1cx n.0bxower 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 producesp9z2eh,slp .qfg 11cxo6x* ic ;2g2f m3nbhhc 60 A of current at 120 V. The voltage is usually stepped up to 4500 V by a tbeh2. 1z ix2g;lhp coqfh x 13 f2ng96mcps*c,ransformer 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 produces 60 A of currtrg i -(6d q/t:5 xamlzi)z,gi .zcs+ment 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 percenzstic ,rg)m65.xi/ t+gd z qz(i: ma-ltage 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 120 V. The voltage is usualsvfqk.pwvwvq 2i ofdv-; 8 (17ly stepped up to 4500 V by a transformer and transmitted through a power line of total resistance 1.0 W. Find th( dp1wfw vs7 vk2vo;.8f-qvqie 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)lg02as-k v/;a aci j6rbqd* d 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 would b/kabqidra6cl*d 2-sj; 0 )vage 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 has a total resist q7pj-1glhopzq wu9,o2mu7;e ance of 0.60 W. A generator produces 100 V at 70 A. In order to reduce energy loss due to heating of the transmission lhqz7 p -o29m7 qowul,1gjeu;pine, 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-W line ( rcv/q x2f7utat 1000 V. How much less power would be lost if fx/( rvc2 qtu7the power were 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 generatoqb3h iik,y. ux 8g9ou/r is 440 V at 20 A. It is to be transmitted on a line with 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 pbk.xouq,g 3 hi8/yi9 uower?

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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 9(gu3/x you b18aecn.ykzs z 8togl/9a current of 5.0 A. How much energy is stored in the coil's magnetic fieldo y8x./g819sz9guy koe/nat uz3 ( clb?

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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 6.0-4osdp:gk - .gzW resistor and an 18-H inductor. What is this circuit'sok-.:4sgdz gp 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 voltagquw *dw zn1f:4e in an AC circuit where 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. What p ddc- +mog-e,grb1m(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. What3z/v.f dg1o ip c-,rt a/1/guaiuc(x2 vj)egb is the resistance of the lamp?ij-e,(z/i cg3r ot pd1u. vfv gcba1gx2/)a/u

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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 120-w g- qd x+dm7/ 3nm3gnn(cza4qV ac power supply. What is the peak current t+(w ncmg-4m d 3qd7zn3gan/xqhrough the resistor?

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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 powe2ld8m3z3jc oxpk vr :jxar-,8r supply. What is the power dissipated in the resistdrx, c rv3jo m8:lp3a8zj- kx2or?

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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 resistor /savuq:/4yb ecvf5 (z 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 resis/chv ; y2otx:m-x, k7bcicl**b3jnf btor 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-rpt ng8fi 34zsx*m -ek,u;+fl s+* rcvW 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 iny35ltpx f6xg(n2jdjuv v4) x3 ductor 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 coil at 1000 Hz? ;m;fekv: di5kg edaps2r)j3 4

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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 0pkb xcvwez);vs . 8/;:x xqsg-)wckg14.0 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 15w,hb72,huf joq 6remg 3luiq7 0zexqfz,0h .37 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 at a frequency of 20 kHz 2 rjyhyw :u4il y qze786rmqh7l 3f7-gis applied 24 jy ell7hru-if 378w ryq:gq6hzmy7to 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 5kn;v8rccod4ie 1mw )-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 reactance of a 4.7-mFv4o xdtq1x1 (l+l irng (37nft 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 z+6td mk:;,dkothiz+ 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 have a reactance of 1200 3t j h(v/loox1ugp++p 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 0.010-mF capacitohx3 lsx v7 jp))mwl+y*z.:xli r be 100 W)xv7wl .)mpi x:xys3hllzj*+ ?

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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 thry8u 2pjs.m/ yhough a 0.0010-mF capacitor 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 circuit q9 dvyg )e +2bo+v4ogcwith 12.0 W resistance, 15.0 W inductive reactance, and 10.0 W capacqg2)oo dy9 v+ b+4egvcitive 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-mHads0i shacd54/k39uzi :/ et+vk qmz- coil, and 1.0-mF capacitor are connected in s+ q94v3/di/5 sh0uaeis acmk zd: tz-keries?

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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 100i0ekgmto 8 m;,-W resistor, 20-mH coil, and 1.0-mF capacitor are connected in series?t 0eiom8gk ;m,

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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 resistor199x4x 7gn.fc*avxu2vuwa;j iay x u( is connected in series with a 20-mH inductor, what is the impedance at 472u91gwajny ( vfvc*xu.9xi; auaxx1000 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 isj8* bzqz05j;3vz mfqb the phase anglq8 j;zvz* bj3q5mz 0fbe 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 circuit with a 20-mH coil and 1.ug-k jgsiuk) bbbg,- 1u8z+,p 0-mF capacitor for a total impedance uuz)g-k g1spk,b, - j g8bu+ibof 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 capx/ v.q97/vy ba-do tjvacitances is needed in series with a 100-W resistor and 15-mH coil to get a total impedance of 110 -v.xv/ b9y / atjdvqo7W 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 series with a 450-mH induc49cxl.v hj9 9jgwfnvuk fto8ib6y ) -(tor at 5000 Hz for a total i9j c.4-fxklvitj9vw )o 6n8gf uybh(9mpedance 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 with a 100-kW resistor at 1.0-MHz for a ton6/rnn4m+reldh8hx 4;f lc 1otalrednn4+h6n8cx flm1or /l4h ; impedance 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. Whaa6:k mi.6r:9drl bc 5oskfl ,qt is the impedance ati:6ksld qa boclm frk96, 5:.r 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 a 10-mF capacitor atbj5ba; p24raxd 0ga32ds1yn r 1.0 kHz for a total impedaa2dab g; pb3 nrx 1adj4sr5y20nce 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 capacitor at 1. wc wpwqm37wye;8 n9 ekx09r6m0 kHz for a phase a 609wwc3x e;mw ym r7pe8qnk9wngle 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 res3uq04nwvf1 xqtz;e :gistor at 1.0 kHz for a total impedance of 45 ezq 14:tx0vf;q 3wgnu 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 H rx(o szn 3/iu8zcw4j1z. What is the phase aw184 sjn ( iz3/ozxrucngle?

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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 ckv d+x;fi p (lm:ov7g6w 2zetby20.jzyo2 ,vuoil, and 1.0-mF capacitor are connet od.wkyi20(b22zf p+lxg : o6mv7vu; ,jvze ycted in 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*eiky8.z npw dzo53y ,ut3 p7k-W resistor, a 10.0-mF capacitor, and a 0.350-H inductor. The circuit is connected to a 120-V, 60-Hz power supply. What is the rms current in the cirkdz3 k 5pzyn7.i,y*ep8 t3uwocuit?

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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 capacit/t f48ydp1 n *m,+ ybcqkejp5nor 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 circuit?q 1n8p dkp+m4jn/5*ftb ,cyye

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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 containif qr:2 3iosz6hmv- f +x:kd ,fdrvl2v6,ubil( ng a 50-W resistor, a 10-mF capacitor x62 s lrvk2q6 ri,blv ,d3fhodimf +:-:z(vfu, and a 0.45-H inductor, when 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 be(b5cs9hfua1x h* q*in series with a 500-W resistor for a phase angle of1c(* q habfx*h bue59s $40^{\circ}$ 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. At what fr68kgre( e6pej)fy 4hlq) eaa+f-udh 2equency should the circuit bu)d k 6(g-e6aee lqfh +2p4e8jhar)yfe driven 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 in an ac series circuit with 12.0 W resist1kx eb75ewb0 tance, 15.0 W inductive reactance, and 10.0 W capacitive reac7 xw tbbe150ketance, 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 an AC circuit is b9g,xum ,v4wr o,u fuq77dik-$63^{\circ}$. 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 of 30 Wuhrzqsxc 1zl j(68w ,7e x*/xk. What is the po *1,lzwkx 68hqrecz(/jxsx 7 uwer 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 resistor7-p4lz-e6njo;h s6q ame2 aa s, a 10-mF capacitor, and a 0.45-H inductor, whla s62m6jp7en-s ;o4qaza e-hen connected 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 0*dn*atyolgc *oo:98 q3 vn fland a 15-mH coil in series?n flqn*8*vtaoclo*:0 d3o 9gy

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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 e *)0oxm:pili for a resonant frequency of 10 kHz?*: mx)li0iep o

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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 serie.yi yoeue tmo:0 5p(j-s with a 3.7-mH inductor for a resonant frequency ot5jy oi(:.-p0e emyouf 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 be placed in series with a 30-imm6s4 p0ei0o*e 4x x.3zwklhW resistor and a 40-mH coil if the lz*hx. m 3e0kmx 64swiip4eo0resonant frequency of the circuit is to be 1000 Hz?

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