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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 maks -g(in7eav 25 x(fwcgnetic 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 the + i 2 zs)xq3wyv-btpe-$emf$ induced in a loop of wire is proportional to

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3#
 
单选题 ( 1.0 分) 切至整卷模式 搜藏此题  
  Doubling the number of loops of wire in an4nzqvr;/gk+,v+ cr.b3s ee p senr8/ coil produces what kind of change on therb/+ rq4vn3s,ne r+ve/;8 gk.peznsc induced $emf$, 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 thzdri.rd m 0/kisj/b-8e magnetic field through a loop of wire produces what k0s8im z/d/rbd-j.ir kind of change on the induced $emf$, assuming all other factors remain constant?

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5#
 
单选题 ( 1.0 分) 切至整卷模式 搜藏此题  
  Doubling the diameter of a loop of wire produces what kind of change r/sshak*(;mr on the inducha rks* (;r/msed $emf$, 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 frt1cjo gp6 wpid-*5t/5arws8h ;)l fo rom 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 induced current ryc14j6ex z*tz1.t *kbk+zpk in a conductor will be that which tends to produce which of the fokb+ tkz61z**4ez 1xjp kryc.tllowing effects?

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8#
 
单选题 ( 1.0 分) 切至整卷模式 搜藏此题  
  A circular coil lies flat on a horizontal table. A bar magnet is held above c. p :;,kiaz eyy9az+zits center with its north pole pointing down. The stationary m,:cp z;zak z y+y.iae9agnet 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 horizonta0 /uhvmnpoh2j4 l.cxd 72cl5 ll table. A bar magnet is held above its center with its north pole pointing down, and released. As it appo2h n 5lmv. cuc7dp/hlx j2l04roaches 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 thwr9we ci3z;+ je magnetic field vector points straight up. The magnetic field vanishes suddeerjz9 wi+w; 3cnly. 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 leve8i4ktjrn/x() s5)s sh x*xiwpl table top in a region where the magnetic field vector points straight up. The magnetic field suddenly grows stronger. When viewed f*hir5 x/n jit)s8 wx()4xssp krom 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 i,:vaic83m3sdl 8dy p 3si,wiwhere the magnetic field points straight down. The magnetic field disappears suddenly. When viewed from above, what is the direction of the induced current is8v:wiipciia8,ddm333y,s l n 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 .o upz+: 3oejmls 4ncsj3(f8 lcarries 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, tcp(z4ljsm+8on s :e 3.l3ou fjhe 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 loo ;yw797f i ljav-.vnkkp of wire with the north pole entering first. As the north pole enters the wire, the induced current wil i7ka.l k-;vnjyv f9w7l 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 rotxh.jl2be*0: j fc6evp ,k*iem ated 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 the loop's axi* v :hci6bj.xpj,f0mk e*2ele s 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 co0bwhxwo -ua 8lcyg/*f,k+go -nstant angular speed about an axis whosea w/lg0 hkwoxg,+yo* cubf 8-- 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 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.am,xf b3+-nai
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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 t 9z;*,pogd kvpn+,egyj(, uy phat 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 fielrgsnu - 7zrv+7d. 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 iny k )h4vachw 3:.xhf9t the east-west direction) is moved northward at constant velocity through a magnetic field that points straight down. Make a statement concerning the potentf4cthw hh k.:x)93yva ial 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 constant angulwn8o-/ 7sub 8ane.yrvxxr8zbr) ym:5ar 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 transfo0eja/q2 q0 bb4omz(k brms

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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 th+p(mjzfh mr7 +rough 60 revolutions each second. The frequency of tjp zh+f+7mmr( 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 deviakgx0/7mj0m ,9y-mdu ;o imeace 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 devi5d5p)tkbv s:s*zn);pe bn9 y ice 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 coi 1;rzhwbpo0 5zl contains more loops than the primary coil t0;wobzrzph5 1hen 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 c:c2j x/wqy8ut-g x*4n.raddt ontains more loops than the secondary coil then ia-t:yjdrc t4.dunwx2q 8g/ *xt 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 powkgxn:j7t8i-occq , .oer 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 resonanth 08hglnsag3- 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 to an ideal bat7 e :y/yb +:w5rg zg22q sdib:km4mujatery of constant terminal voltage. At s22 yby:qm gda47z:+kgm/u e :5jiwbrthe 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 connectt w4xi 8hf8b)zed in series to an ideal battery of constant terminal voltage. At the moment contact is made with the battery, the voltage across the inductor is8tz4bix 8fhw)

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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 resistax-5 q fdm5ghk4xoci.7d/ 0mq 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 and resistance R is connected to 3 --khijmx 8nvan $emf$. 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 battet mben 2.bp8a+ry. The time constant for the circu .a epn8b2mt+bit 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 inductorskxkorp dhb2 k vcye1+l v+;+(n;xg-8 are connected in series to a battery. The battery is suddenly removed from the circuit. The time constant for of the circuit represents the time required for the current to de; nsh2d++c kk(rg kbye v;8op-lx+1xvcrease 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 followingc+ (6vhgbbxfz9-u8zg have the same units except:

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38#
 
单选题 ( 1.0 分) 切至整卷模式 搜藏此题  
  A resistor is connected to an AC power supply. On this c vhv1:mdb4pty5t z6t674s awyircuit, 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 sup8:try9ek-af*94zjt dcx5gkj0 hcl *b ply. In this circuit, the currenjt9-9ckbe0 8zk *dl*agj rf yxc :h45tt

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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 what fact ./c4y7z9t dvm;: qt:lpwd zvjor when the frequencz4d.:ztmq v vl 7j9c:p/ dt;wyy 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 ACm6 *w.sha4v2ddq yc 2kkdm 6*t voltage across an inductor is doubled, the inductive reactance of t6ymv *s2k 2qd a6kwtm4c*hdd. hat 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 indunkn9 fci372aralkd)wy;3 zk,ez0p9u ctor approaches zero, the inductive reactance onrnz 9, ea2kick70pw yal3f )du39; kzf 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 circui+ y/zbl g,i.avt, the curreibv.ga ,zl/+ynt

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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 80qjwf u5 u zr1w+d-vlwhat factor when the frequency is 1-d05r u8l+wfzw qvj utripled?

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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 appkd e531okfr;)t j-k wp9k:oow8) mpwy roaches zero, the capacitive reactanco3wdko9)1k f m)k ry8;petww o-5jkp :e 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 inducto8b+jnr6 v76 nzd:sw, l ixg;0h8ifjgyr and capacitor in a RLC series circuitig07;vl6inxbfj ,g68w r 8jhsz + ynd:?

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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 6)ev 0 kjef*voyq2t:zcircuit 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 the circuit -q0u5o yf*ktwm *r(dgvbah 11increases if R increases. When is this statement trfu - wb5o1a**0 g1khym(vdqtrue?

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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 1r)k7tan5min,c ;jgmr:/u lman c35 y the 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 increasc(;zdr.d 4/7gbs e fkzj rgy+)es 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 bot gnrh9v4 ux8axq3aa28 h double in an LRC series circuit, the resonant frequency of that circaargx832n a4hx9u vq8uit 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 isqj v kt(t /xw6+ytpf3wi sa:50 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 circ8sdi ib 7it5i5j65qm+olxjt1 uit occurs when

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

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55#
 
单选题 ( 1.0 分) 切至整卷模式 搜藏此题  
  A circular loop of radius 0.10 m is rotating in a uniform maq m41jjfal-i *gnetic field of 0.20 T. Find the magnetic flux through the loop when the plane of the loop and the magnetic field vector are para4 qfajl* i1-mjllel.

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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 0yi:;8zlxugl1 .20 T. Find the magnetic flux through the loop when the plane of the loop and the magnet8i:xlg zu1y ;lic 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 rvx6. l-ap gl.zadius 0.10 m is rotating in a uniform magnetic field of 0.20 T. Find tga 6x lz-pv.l.he 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 ansi)1b;u8qiw t0 ktw1p 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 changes fr4,7sqdq3u lx5u ve5qtom $4.0 \times 10^{-5} \; Wb$ 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 wi1yy)-oatmnft i s6*8xgy6ob ;th 200 turns of wire on a square frame with sides 18 cm. A uni;byygn o-s*8t6 f1a)o xy6i mtform magnetic field is applied perpendicular 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 t0-ugxr/-zc d burns 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 arer vxeyxoyiemx*,i 6w;/pzmf3rc 3+93a $0.20 \; m^{2}$ 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 nz :jv*g2mg7xwcc : 11lj3zgw60 m flies horizontally at a location where the downward component of the Earth's magnetic fielw3:jl*c7c2 gmgw:1v znx j1gz d 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 constantp,wjj s;9 cz 5jfl;pn+ angular velocity of 2.0 rad/s about a vertical axis through one of its ends while in a constant magnef;pwcpnz 9 ;+ s5jjl,jtic 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* yfrh(a,k s)b 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 34d;liii )wjatnvdw*r2ukg)/: mcz5of 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. Eabsnao- ldd7qn3;rbp. /wc luq 6h2 0t8ch loop is 12 cm long and 8 cm wide. The armature rotates at 1200 rpm about an axis parallel 6a8wsrpd d.u 2qb/3cnton7 ;q0llh -bto 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 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 arfx js 1-j6vxu/g8bo+gq s :jw6ea $0.090 \; m^{2}$ 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 generv cn(,;co, jhwator with an output of 12 V maximum when rota,;n(c ,w cvojhted at 60 Hz. A magnetic field of 0.050 T is available. If the area of the rotating coil is $100 \; cm^{2}$, how many turns are needed?

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70#
 
单选题 ( 1.0 分) 切至整卷模式 搜藏此题  
  You are designing a generator with a maximumraq lqa; g-77 3*idskg $emf$ 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 resis-m+0o zfaw+q stance of 6.00 W. The motor operates on $120 \; V$ AC, and when running at full speed it generates a back $emf$ of 105 V. What is the starting current of the motor?

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72#
 
单选题 ( 1.0 分) 切至整卷模式 搜藏此题  
  The windings of a DC motor h,7ezcww77*wv(d mqnr ave a resistance of 6.00 W. The motor operates on 120 V AC, and when running at full speed nc7 , 7evrw7zq(*wwmd 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-n( xitkiuf 89)V power supply. The operating current is 1.0 A. What is the start-up currx k( ii)f8ntu9ent?

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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.dmw9xa1rvamb;)v h 7. The operating current is 1.0 A at full speed. Wah71mad ;m)rvbwx9.vhat is the back $emf$ when the motor is running at full speed?

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75#
 
单选题 ( 1.0 分) 切至整卷模式 搜藏此题  
  A DC motor of internal resistance 6.0 W is connected to a 24-V pow(f7z2nb)u;am9gh)x*j eiv kiw;e9 wk yn7 l.eer supply. The operating current is 1.0 A at full speed. What is m2zwyh .niv7naki (f9l*ej)) ;gu;7xb9ke w e 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 voltagfsv-x; xhf* -yt2:c o5f2kf 1lbx(lgje 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 primalz ym.2a+xxcgr2 p)s1 ry of a transformer causes 14 A to flow in the secondary. Ho+zm1rsx2)l gca y2xp .w 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, how many turns xdbwnv 0r 4n+cx4jr ca ra0ys73l0f ,7are necessary in a 110-V primary if the 24-V secondary has 100 turns?40sncr7 3rb740x njf,a x yr+wa0cldv

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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 coiljpipp, gic;d.-ugj :-: yu0.omi u3 my and a 2000-turn secondary coil. If the current in the secondary is 3.0 A, what is the cuyg 0 .opij;y- pm3p, uu:u.dcii gm:-jrrent 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 transformer. Assuming 100% effiil k5s 45:yybgg j- ./yajlm2iciency, how many amps at 24 V can flow 5i lj-52a ls:bjg 4mi/kyyg .yin 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 siglmk9xj +qd(sb.: (8etameo-s n transformer provides 7500 V at 10.0 mA. The primary coil operates on 120 V. What does the primaryb(a8mxqtdj(sme9-l : se . +ok 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 coil and 300 turns on its secoa*p xpl6o 2l;04eh- yokufm7r o5r6q ondary coil. If 120 V at 2.0 A is applied to the primary, w5 0r6ol- oyoe7 xh2uo4f;rql6*mpp akhat 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 ..dz)tk9 p/veij w6lr on its primary coil and 300 turns on its secondary coil. If 120 V rj.pwit) elk9vz.d6/ 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 itsiq8mxh+;x sys m k5(g1 secondary has 200 turns. If the input current at the primary is 10m q1gks y +;5xsx(i8mh0 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 and1 jbux frm (nyu0pnr 3y8t3w.hw181oq its secondary has 200 turns. If the input voltage to the primary is 100 V, we can expect the output voltage of the seconuw3y 11xm y0nqurtn w8f3h (8 b.j1oprdary 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 turns.p fhkr)ib ig)wdd/-,erbxz- g 60tn(2 If the e(-/fdgg t2ribrh)bdxzwk-) n i6,p 0power input to the primary is 100 W, we can expect the power output of the secondary to be (neglecting frictional losses)

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87#
 
单选题 ( 1.0 分) 切至整卷模式 搜藏此题  
  A generator produces 60 A of current at q ;irp0b0(ml,c *lscu5cmqv ul*.m9u 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 number of turns in the secondary if the primary ha*, upr0lc9.s* v(uc5i; m lumcqm0qlbs 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.bh;: wb8,so ;+ okjl2w0ho wsu The voltage is usually stepped up to 4500 V by a transformer and transmitted through a power line of total resistance 1.0 W. Find the percentage power lost in the tra2 l+wwhb,:wb 8ouso js;o0;k hnsmission 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 ii,r tlt1-brw1s usually stepped up to 4500 V by a transformer and tranlwb, 1 ritr1t-smitted 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 idlg; 4bxd1cc v6dup vjt/rbu.2vzp48+6xx- 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 bevd8 4dzix+j bdlc/x4r6p1xg; vb c6 uu2t .v-p 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 resistance of 0.60 W. A ta i7.m8aiu:)w wi 5zpzo27ot 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 w )pz8m2 awi:oti5t7 i.wazu o7ith 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 at 1000 Vtdsl 15m( b6iq. How much less power would be lost if the power were transmitted at 3000 V instead olbmqs6 1i dt(5f 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 b06 /lg(wuxnyk: k 6i6q tb27rov 1rutke transmitted on a line with resistance of 0.60 W. To what voltage must the generator output be stepped up with a tra6 wtntb oukrg26ivr yq/x k0u:17(6l knsformer 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 stord( jnk ns3zo(vp65p2 ned in the coil's m dzsn(3n65 (2jp npvokagnetic 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 resistor20/ n jigc3 cuxe*dc3y and an 18-H inductor. What is this circuiidxncgc* 20e/yuj c3 3t'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 voltagtt8 zq/( p99 w)xpbakte 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 is the p gio:ap;l jb36eak 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 the resistance ofg90l-d9 kvf jtvj4j4 p the la4p-g9vdjkfvj j4tl9 0mp?

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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-s qyjj(h5m+5w V ac power supply. What is the peak current through the rejj5s+ w5y mqh(sistor?

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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 con gnrf;x( y1gyk3jf*+b nected to a 120-V ac power supply. What is the power dissipated in the resistor?b*3rf;gxy(j kf+ 1ngy

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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/klnl f7r ev5+m 0dkw14q jw,0tlvu k)l-wg,q 50-W resistor is $I = 0.80 \sin (240 t)$. What is the rms current?

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102#
 
单选题 ( 1.0 分) 切至整卷模式 搜藏此题  
  The current through a -an4 8biofdnr*43w. p1rfzrm 50-W resistor is $I = 0.80 \sin (240 t)$. At what frequency does the current vary?

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103#
 
单选题 ( 1.0 分) 切至整卷模式 搜藏此题  
  The current through a 5093a oyafhlf 3d1g r/p288zrud-W resistor is $I = 0.80 \sin (240 t)$. How much power on average is dissipated in the resistor?

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104#
 
单选题 ( 1.0 分) 切至整卷模式 搜藏此题  
  What is the reactance of a 1.0-mH inductor at 60 c1)ei+mk jks:*w( fi zHz?

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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 1j rs7u-z(noucw ,8x6e000 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 14pxzh; ho7poa: 1m b.a2.0-mH coil have 14.0 W of inductive reactance?

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107#
 
单选题 ( 1.0 分) 切至整卷模式 搜藏此题  
  What inductance is necessary for 157 W of inductive reacta fihq3ouk 8m2pvmh. 1.w6)lhxy +1i66y lh sbqnce 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 aep q2 m,9;k d6lte-srgt a frequency of 20 kHz is applied to itp;e l-rt, d29smqge6k?

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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 en/6((z x obymto 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 reactance of a 4.7-mbp/4u mlb(1 jiF 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 t6 c.a.ynmhirem9r:u 7yqe -8yo 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 1rimpr),kg) t 10-mF capacitor have a reactance of 1200 W?

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113#
 
单选题 ( 1.0 分) 切至整卷模式 搜藏此题  
  At what frequency will the capacitive rexcns0k4z uq89d 9yy( pactance of a 0.010-mF capacitor be 100 W?ndz k409cy9uqp8(syx

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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 0.006(jb 4s02sr g oanmzrb3ik. c+10-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 o+.9takymx zfl, p2+r ef an ac series circuit with 12.0 W resistance, 15.0 W inductive react,r.y 9+ x2zal+ etfmpkance, and 10.0 W capacitive 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 atz*r64 ge,qs ay 1500 Hz if a 100-W resistor, 20-mH coil, and 1.0-mF capacitor are zr*sa6e ,qy 4gconnected 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 ae)tqhqv/7 t, e-zybmho9 4t0d 100-W resistor, 20-mH coil, and 1.0-mF capacitor are connected in sere/-9dtzb4 he,0q7mty tv) qo hies?

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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 icsh.wlb4r/i1ws y3) qs the impedih4s w1y/l)cq.bsr3wance 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 ae1 jpxaa,fz2 ;bci8fb93tdw * 20-mH inductor, what is the phafbtj; ei1 *wzcp b3 9xda,28afse 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 circuit with a 20-mH coil and c qys uofzqgu7(rruv n+.-a+/+a1w 4y1.0-mF capacitor for aq 4/cuzrv sqwru1gyao7f.+an y -(++u 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 *292.oavt kk;ms nyaim 2s3n eseries with a 100-W resistor and 15-mH coil to get a sim2kn2syaov* emk;39n.t 2 atotal 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 series with a 450-mH inductor at 5000 c1be( nt5d/ y zc/jveok9 5i5rHz for a total impedance of cvnjtdb i/e5k5(z o9r5yec /1 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 okm bec0 ;7g6feyf 4y(100-kW resistor at 1.0-MHz for a total impedance of 7e(0 fbo fge4mc6y;ky150 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 sefh/v7 od ozj dd4rv43w+ ldq1(ries with a 20-mF capacitor. What is the impedance at 1000 Hl jvh47do3d 1 +wdq4or(v/df zz?

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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 wi6xndc14uy dw; th a 10-mF capacitor at 1.0 kHz for a total impedan6dd4n; yc xw1uce 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 calxomitas t5t 6x*6*p -hnd wot;3 yn2:pacitor at 1.0 kHz for a phase angpd23 6*th-sm:*ia 6ltx w;t yxn 5onotle 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 resistor at 1.0 m:qna2x (t hgo 76xjnu*0cv/ikHz for a total impedajn *tix 7c/g h:nu02mx6ovq(ance of 45 W?

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128#
 
单选题 ( 1.0 分) 切至整卷模式 搜藏此题  
  A 10-W resistor is in series with a 100-mF capacitor at 120 Hz. What is thvpuc22n.em-75s wabhe phase a5v aspbm2. -2ec7nwhu ngle?

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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-mHxn o /,8.ovk:d+vhbow coil, and 1.0b8 /o.,o onv whxk+:dv-mF capacitor are connected 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-W resistn7p+*lu)u wxnor, a 10.0-mF capacitor, and a 0.350-H inductor. The circuit is connected to a 120-V, 60-Hz powern7u+u*p ln) xw 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 capacitive reactance 30 W,izs +8-8dy/ 7 oueefip and an inductor of inductive read-ypfiui s 8z+8oe7e/ ctance 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 angle for a series RLC circuit containing a 5/8 ig4g fz:sjaw b5-ih0-W resistor, a 10-mF capacitor, and a ij-asg5 if4hbg:w/8z 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 in series with a 500-W resistor for a phase aq)hrsgx g. m61ngle o6q)gxms rh.g1f $40^{\circ}$ 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 fre, f* ax7w;qfytf;l q+dquency should the circuit q, 7qfwy;axd*f;l+ft be 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 reu5 a,d1b) ythksistance, 15.0 W inductive reacahb ud, k1)y5ttance, 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 an AC circuio7l:(r(yiu d5o* jb vgt 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 resistuv1 u1 srbu,v0ance of 30 W. What is the powe1vv ur 0b,usu1r 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 Rk0/c1pe 5dgjx LC circuit containing a 50-W resistor, a 10-mF capacitor, and a 0.45-H inductor, when connected 51 cpxg/d0jekto 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 iry5 rd9b4eu qfs:- 8p/w xkjo j,r/o/capacitor and a 15-mH coil in series?/obj5uskr:dq, i9 r-x/pjoey4/wf 8r

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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 series6g2,ef)m1rbi kc ) bbn with a 4.7-mF capacitor for a resonant frequencye,)bm fb)2 r1n6kbg ci 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 serac5w 3k--hkf +l 3nwufies with a 3.7-mH inductor for a resonant frequenc-wnuk-afl c5 3wf+3 hky 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 be placed in series wit ,ve1n padu3(* kaz+ith a 30-W resistor and a 40-mH coil if the resonant frequency oa*3naz(v+pktu1 ie ,df the circuit is to be 1000 Hz?

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