题库网 (tiku.one)

 找回密码
 立即注册

 

      

上传图片附件

未使用图片

小贴士: 允许的图片文件格式为: gif, jpg, jpeg, png, webp,上传完成后会在上方生成预览,用鼠标连续双击缩略图,或拖动缩略图,该图片就被绑定至本题,显示在题目下方

本次作答已使用

小贴士: 此栏目显示的是当前作答使用的所有图片,绑定到某一题目的图片同时会显示在该题目下方; 删除使用的图片会将其转移到<未使用图片>类别


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

标记此题
1#
 
单选题 ( 1.0 分) 切至整卷模式 搜藏此题  
  All of the following are ui0 cc a3qu21d5wb0 tpnnits of magnetic flux except

参考答案:    

标记此题
2#
 
单选题 ( 1.0 分) 切至整卷模式 搜藏此题  
  Faraday's law of induction sta ;pga6e; r(b9p2o0yozkn n 0lftes that the $emf$ induced in a loop of wire is proportional to

参考答案:    

标记此题
3#
 
单选题 ( 1.0 分) 切至整卷模式 搜藏此题  
  Doubling the number of loops of wire in a coil produces what u:i ev-c9e4hic.gfb; kind of change on the induced .evc 4he9cu;bii-g: f$emf$, assuming all other factors remain constant?

参考答案:    

标记此题
4#
 
单选题 ( 1.0 分) 切至整卷模式 搜藏此题  
  Doubling the strength of the magnetic fietzgtk9.bjq:4 h9b zl,k n: gu.ld through a loop of wire produces what kind of change on the i. u,:gtk9 bqzl:tgz 94nbk hj.nduced $emf$, assuming all other factors remain constant?

参考答案:    

标记此题
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 prod4 jdp: o/ec5jhuces what kind of change on the indud: 5e4/cj pohjced $emf$, assuming all other factors remain constant?

参考答案:    

标记此题
6#
 
单选题 ( 1.0 分) 切至整卷模式 搜藏此题  
  As a coil is removed from a magna2f m4+ i eszo(thx;6wetic 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

参考答案:    

标记此题
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 . t/hwf,dn,l1bdwnu0an induced current in a conductor will be that which tends to produce which of the fo nu., t bd1wn,hl0f/dwllowing effects?

参考答案:    

标记此题
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 a*t70n2 b qzv+xh mbrp4l4ijscq,; 8dd bove its center with its north pole pointing down. The stationary magnet ddm4ibhcq ,txqr n0zb *s27l8j ;4+vpinduces (when viewed from above)

参考答案:    

标记此题
9#
 
单选题 ( 1.0 分) 切至整卷模式 搜藏此题  
  A circular coil lies flat on a horizontal table. A bar magnet is held above g26uflmt: *jv its glv: t* 6ujfm2center with its north pole pointing down, and released. As it approaches the coil, the falling magnet induces (when viewed from above)

参考答案:    

标记此题
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 whqj pxc:5-qa:pif3 w+b ere the magnetic field vector points straight up. The magnetic field vanishes suddenly. When viewed from above, what -qb53xc :p: ij a+fpwqis the sense of the induced current in this coil as the field fades?

参考答案:    

标记此题
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 wherermf;dl (8nj f*s/2jb4x gx 7uw the magnetic 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 increase8 d b4wxl /nmju2(r*7fjxsg f;s?

参考答案:    

标记此题
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 yosfxbr*0dw62/ e..8rnh ibdin a region where the magnetic field points straight down. The magnetic field disappears suddenly. When viewed from above, what is the direction of the induced current ib sy8 0 d.ehroirf26d.w/ nx*bn this coil as the field disappears?

参考答案:    

标记此题
13#
 
单选题 ( 1.0 分) 切至整卷模式 搜藏此题  
  A long straight wire lies on a horizontal table and carries an ever-increasinm6ij1.6td r4ve k-s pfg current northward. Two coils of wire lie flat on the table, one on either side of 6dtejm1 -if sr4p.v6 kthe wire. When viewed from above, the induced current circles

参考答案:    

标记此题
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(u+okckl4uy0z:6 qo 5fiz x(c first. As tzolc 0(i5k4yxqz fu(k c:+6uohe north pole enters the wire, the induced current will be (as viewed from above)

参考答案:    

标记此题
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 7d/g)j hqgv-5jvu nf)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 nqvuv) gh)57j -d/ gjfof the loop's axis of rotation if the induced $emf$ is to be zero?

参考答案:    

标记此题
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 angu1vpf t02ctk,qgt/nu 5lar speed about an axis whose direction can be varied. In a region where a uniform magnetic field points straight down, what must be t,p2vqgt5/0knu 1cft the orientation of the loop's axis of rotation if the induced $emf$ is to be a maximum?

参考答案:    

标记此题
17#
 
问答题 ( 1.0 分) 切至整卷模式 搜藏此题  
State Faraday's law.nxz y,z5y)jb4.ya ,jc
参考答案:    

标记此题
18#
 
问答题 ( 1.0 分) 切至整卷模式 搜藏此题  
State Lenz's law.
参考答案:    

标记此题
19#
 
问答题 ( 1.0 分) 切至整卷模式 搜藏此题  
List the three ways that a .rn67iqahq5fn $emf$ can be induced in a loop of wire.
参考答案:    

标记此题
20#
 
单选题 ( 1.0 分) 切至整卷模式 搜藏此题  
  A wire moves across a magnewp7+wk g jbu8+y, kkt-tic field. The $emf$ produced in the wire depends on

参考答案:    

标记此题
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 dx5 ou(,vy9p .ewon2cr irection) is moved northward at constant velocity t(p v e9,.rwx ycnou52ohrough a magnetic field that points straight down. Make a statement concerning the potential induced across the rod.

参考答案:    

标记此题
22#
 
单选题 ( 1.0 分) 切至整卷模式 搜藏此题  
  A horizontal metal bar rotates at a conc1+zx 1fmffk;u2uq1qstant 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

参考答案:    

标记此题
23#
 
单选题 ( 1.0 分) 切至整卷模式 搜藏此题  
  An electric generator transformsu /u 7h7 zndjq;5wu2 0q:pnxzf

参考答案:    

标记此题
24#
 
单选题 ( 1.0 分) 切至整卷模式 搜藏此题  
  A generator coil rotates through 60 revolutions eachx t) ia4 c)y/kmg7+rrjybgk 52 second. The frequency of th)rk mgygt+72ciar) 4 b/y5xkj e $emf$ is

参考答案:    

标记此题
25#
 
单选题 ( 1.0 分) 切至整卷模式 搜藏此题  
  A transformer is a device used 0:uc lvxy (.zrpm4+3c.kpbz3fa 9vlj to

参考答案:    

标记此题
26#
 
单选题 ( 1.0 分) 切至整卷模式 搜藏此题  
  A transformer is a device tha0+6obrm( d6imhyg :m t)enpy:t

参考答案:    

标记此题
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 more loops than0 - 45br)h3oluxutyzi the primary coil then it is4 u5r0li xu3yozh-b)t a

参考答案:    

标记此题
28#
 
单选题 ( 1.0 分) 切至整卷模式 搜藏此题  
  In a transformer, if the primary 7q)is o u8xx/m2w) jwucoil contains more loops than the secondary coil thus2 xwx8 m iuo)/w7)qjen it is a

参考答案:    

标记此题
29#
 
单选题 ( 1.0 分) 切至整卷模式 搜藏此题  
  In a transformer, the podx ddz-o3 dq ;m(s5zzl 0r1rz3 /8eocower input

参考答案:    

标记此题
30#
 
单选题 ( 1.0 分) 切至整卷模式 搜藏此题  
  In a given LC resonant circuit,ky.fwx z aathgd9y/-(.80dm d

参考答案:    

标记此题
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 battery of c6)rcm wask+u 8onstant terminal voltagw8m+aur )k6c se. At the moment contact is made with the battery, the voltage across the resistor is

参考答案:    

标记此题
32#
 
单选题 ( 1.0 分) 切至整卷模式 搜藏此题  
  A resistor and an inductor are connected in series to an idea+d awf51f2ozqx*: mnfl battery of constant terminal voltage. At the moment contact is made with the bx5q2* dn+1 z:off famwattery, the voltage across the inductor is

参考答案:    

标记此题
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 ress-kkgz5 /r:n(qm 2ryl1zmc q 0 z5e0ucistance 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?

参考答案:    

标记此题
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 resistancjr) 5z;:nq r bh9dbk*5nrud5be 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?

参考答案:    

标记此题
35#
 
单选题 ( 1.0 分) 切至整卷模式 搜藏此题  
  A resistor and an inducto;wcdvlkc 3p1:r are connected in series to a battery. The time constant for the circuit represents the time reqclp; 3:kd1cv wuired for the current to reach

参考答案:    

标记此题
36#
 
单选题 ( 1.0 分) 切至整卷模式 搜藏此题  
  A resistor and an inr0kogob1hz ,u +nh 74mductor are connected in series to a battery. The battery is suddenly o0b m+zh7rgoh 4nu,1kremoved from the circuit. The time constant for of the circuit represents the time required for the current to decrease to

参考答案:    

标记此题
37#
 
单选题 ( 1.0 分) 切至整卷模式 搜藏此题  
  All of the following have the same unitszsq4giy.k6 (h vz: yl1 except:

参考答案:    

标记此题
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. 16r ma6v gyel(6ev1evOn this circuit, the current

参考答案:    

标记此题
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 suqm2 m06o:zy q90nqfkevn;bm * pply. In this circuit, the currenqnnb0mmzy; f qovmk 9q*06 :e2t

参考答案:    

标记此题
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 mr 9o jq)z,s7jby what factor when the frequen97j qoms)rjz, cy is tripled?

参考答案:    

标记此题
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, 1st5gqcs(at,/v*l ig,gil 4 mthe inductive reactance of vc g*t4s,1 ll isgq5mi/g(,atthat inductor

参考答案:    

标记此题
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 a)pufspn9 hk (:p e3l-tgly9cmb/ *i4mn inductor approaches zero, the inductive reactance of that coek 3pt4snchmu) 9ip /my-lbfgl( p: 9*il

参考答案:    

标记此题
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 1eb +zjdo q/ tcz r)(mas2th6;power supply. In this circuit, the currezh rc1t 2mjbzq t (do/;6ase)+nt

参考答案:    

标记此题
44#
 
单选题 ( 1.0 分) 切至整卷模式 搜藏此题  
  The capacitive reactance in an ac cir/ ++ m:mcjm)z qmnvdb0cuit changes by what factor when the frequency is tm m/j bmd0+ n:+)zmvcqripled?

参考答案:    

标记此题
45#
 
单选题 ( 1.0 分) 切至整卷模式 搜藏此题  
  As the frequency of the AC voltage across a capacitor approaches zero,e.zsg-/1lfgus/ol* p the capacitive reactance of that l.1- oefgs* zplgus //capacitor

参考答案:    

标记此题
46#
 
单选题 ( 1.0 分) 切至整卷模式 搜藏此题  
  What is the phase angle between the voltages of the inductor and capacitor inoss +wgf0m qa:n s791f a RLC s s:m+sn1fq g7fo 09asweries circuit?

参考答案:    

标记此题
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 dwc b1lq4p4uy3efined as $\cos M = R/Z$, but the phase angle can also be calculated from .

参考答案:    

标记此题
48#
 
单选题 ( 1.0 分) 切至整卷模式 搜藏此题  
  Consider an RLC circuit. The imped)cp3dp o(xb6yance of the circuit increases if R increases. When is this) c ybpo(dxp36 statement true?

参考答案:    

标记此题
49#
 
单选题 ( 1.0 分) 切至整卷模式 搜藏此题  
  Consider an RLC circuit. Th;4cg fcvx+(tn e impedance of the circuit increases if $X_L$ increases. When is this statement true?

参考答案:    

标记此题
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 increag0aw p7-azqc;t)a-m9do vv )jses if $X_C$ increases. When is this statement true?

参考答案:    

标记此题
51#
 
单选题 ( 1.0 分) 切至整卷模式 搜藏此题  
  If the inductance and thej pvdfxtr,.p u t./a)5 capacitance both double in an LRC series circuit, the resonant frequency ju ap.)5f/.xt vrdp ,tof that circuit will

参考答案:    

标记此题
52#
 
单选题 ( 1.0 分) 切至整卷模式 搜藏此题  
  Consider an RLC circuitqsn u51vlm2;uy90.i 7tqcn ja that is driven by an AC applied voltage. At resonance,

参考答案:    

标记此题
53#
 
单选题 ( 1.0 分) 切至整卷模式 搜藏此题  
  Resonance in a series RLC circuit occursquzg w- ;-ixhk-p4/cd when

参考答案:    

标记此题
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?

参考答案:    

标记此题
55#
 
单选题 ( 1.0 分) 切至整卷模式 搜藏此题  
  A circular loop of radiusv rp9k n42 zohk.:bc;j 0.10 m is rotating in a uniform magnetic field of 0.20 T. Find the magnetic fc ;jnk4o2kpv9rbh: .zlux through the loop when the plane of the loop and the magnetic field vector are parallel.

参考答案:    

标记此题
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 rotatindo ukffogpagli ,+v q. q7a99dni);,5g in a uniform magnetic field of 0.20 T. Find the magnetic flux through the loop when the plane of the loop and the magnetic field v l7if+au;d go9d9).vaonqfgp q,,5k iector are perpendicular.

参考答案:    

标记此题
57#
 
单选题 ( 1.0 分) 切至整卷模式 搜藏此题  
  A circular loop of radius 0.1x)4zg g3 n( ql)c,dpqd0 m is rotating in a uniform magnetic field of 0.20 T. Find the magnetic flux through the loop when the plane of the loop and the magnetic field vector are aqxg3 )dq)ld4 ,nz(pgc t an angle of $30^{\circ}$.

参考答案:    

标记此题
58#
 
单选题 ( 1.0 分) 切至整卷模式 搜藏此题  
  The cross-sectional area of an adjustable sing, ilrsaat -r ga3f*8ulxk(w(,le 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?

参考答案:    

标记此题
59#
 
单选题 ( 1.0 分) 切至整卷模式 搜藏此题  
  The flux through a coil h*/k r5k1 ghy,evt:o uchanges 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?

参考答案:    

标记此题
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 fram+qntry.8 l6sucyl i+(og a :+de with sides 18 cm. A uniform magnetic field is applied perpendicular to the uylnr8d(t+ +:ac6+osi y. glqplane 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 $emf$.

参考答案:    

标记此题
61#
 
单选题 ( 1.0 分) 切至整卷模式 搜藏此题  
  A square coil of wire 3gnd +j5,d;esx :fhlawith 15 turns 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 $emf$?

参考答案:    

标记此题
62#
 
单选题 ( 1.0 分) 切至整卷模式 搜藏此题  
  A coil of 160 turns and ars+d fs p,4f)krea $0.20 \; m^{2}$ 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?

参考答案:    

标记此题
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 horizontal y*tf;nie c7o6pa)*pply at a location where the downward po 6y)* ei*f papnt7c;component 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.

参考答案:    

标记此题
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 a cnb)e2:yzk9et a constant angular velocity of 2.0 rad/s about a vertical axis through one of itsece b9 k:ny)2z 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?

参考答案:    

标记此题
65#
 
单选题 ( 1.0 分) 切至整卷模式 搜藏此题  
  The coil of a generator hf3ohs,ge 6yybo2/ l1l as 50 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?

参考答案:    

标记此题
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 wire2tn+ztn r8-ts 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 $emf$.

参考答案:    

标记此题
67#
 
单选题 ( 1.0 分) 切至整卷模式 搜藏此题  
  An AC generator has 80 rectangulv93d4e8mef02zq zouid:xx kh7gcm: 0ar loops on its armature. Each loop is 12 cm long and 8 cm wide. The armature rotates at 1200 rpm about an axis parallel to the long side. If t80f dheizuz 7 x gok :xq2e4cdv0:m93mhe 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?

参考答案:    

标记此题
68#
 
单选题 ( 1.0 分) 切至整卷模式 搜藏此题  
  An AC generator consists om2nb,pt v)dp; y7wp1a f 100 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.

参考答案:    

标记此题
69#
 
单选题 ( 1.0 分) 切至整卷模式 搜藏此题  
  Suppose that you wish to construct a simple AC generator with an oub1gxh u(ufyq))nu/ 4.t, xpgpi dv;.ttput of 12 V maximum when rotated at 60 ufv) /(.dt,1g ;xbh ug).4itxpun pqyHz. 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?

参考答案:    

标记此题
70#
 
单选题 ( 1.0 分) 切至整卷模式 搜藏此题  
  You are designing a generator with a d(ts c(vrix8zc 6:x2w 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?

参考答案:    

标记此题
71#
 
单选题 ( 1.0 分) 切至整卷模式 搜藏此题  
  The windings of a DC motoo7z9juz,j xn ,od.ab,,dg zh a,pa g,;r have a resistance 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?

参考答案:    

标记此题
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. t7/5 nu8mqhklThe motor operates on 120 V AC, and when running at full speed it generates a back t/k5h um7l q8n$emf$ of 105 V. What current does the motor draw when operating at full speed?

参考答案:    

标记此题
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-Vaddb 3z-*e(ll power supply. The operabd ea(d* lz-3lting current is 1.0 A. What is the start-up current?

参考答案:    

标记此题
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. Tqmp oq-+ *smb2he operating current is 1.0 A at full m+2q bso qp*-mspeed. What is the back $emf$ when the motor is running at full speed?

参考答案:    

标记此题
75#
 
单选题 ( 1.0 分) 切至整卷模式 搜藏此题  
  A DC motor of internal rebb ul3 fhfsr;f5(v )7isistance 6.0 W is connected to a 24-V power supply. The o)sif;u5 3bf(vl hbfr7perating current is 1.0 A at full speed. What is the back $emf$ when the motor is running at half speed?

参考答案:    

标记此题
76#
 
单选题 ( 1.0 分) 切至整卷模式 搜藏此题  
  A step-down transformer is nee*xy vi+y h* s0rwz( m*coez,5xded to reduce a primary voltage of $120 \; V$ AC to $6.0 \; V$ AC. What turns ratio is required?

参考答案:    

标记此题
77#
 
单选题 ( 1.0 分) 切至整卷模式 搜藏此题  
  2.0 A in the 100-turn primary of a transformer causes 14 A to /+c5ee g 8akxbflow in the secondary. How many txe+ga/k5bc 8e urns are in the secondary?

参考答案:    

标记此题
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 t q/4ik2 n(sn bv chi4;-9owrnn.k4rge he 24-V secondary egrkio4ni2v9; nn44./- hqcwbr (nks has 100 turns?

参考答案:    

标记此题
79#
 
单选题 ( 1.0 分) 切至整卷模式 搜藏此题  
  An transformer consise/mzj3z+z iw(ts of a 500-turn primary coil and a 2000-turn secondary coil. If the current in the secondary is 3.0 A, what is the current z/jwe(+ iz3mz in the primary?

参考答案:    

标记此题
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 p, yzz8pkz4 utymd++ .*zg3flthe primary of a transformer. Assuming 100% efficiency, how 4f *3zpzu8g,d zz y.l+kpm t+ymany amps at 24 V can flow in the secondary?

参考答案:    

标记此题
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. The0:cddx*qg i 0x primary coil operates on 120 V. Wh0gq:cdx0d* xi at does the primary draw?

参考答案:    

标记此题
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 coi5n.ta. v rvtqn /te6o8au*uh8l and 300 turns on its secondary coil. If 120 V at 2.an t/h. u*v.eqa5t6rv u8tn8 o0 A is applied to the primary, what voltage is present in the secondary?

参考答案:    

标记此题
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 30+8u) he 2h l br.nmnb7fej;jr10 turns on its secondanlne u 2f bb8)1j;mj+er. 7rhhry coil. If 120 V at 2.0 A is applied to the primary, what current is present in the secondary?

参考答案:    

标记此题
84#
 
单选题 ( 1.0 分) 切至整卷模式 搜藏此题  
  The primary of a tranfg bi j)k3wwa ,h3+hsek: +1zjsformer has 100 turns and its secondary has 200 turns. If the input current at the kzaf gw)j ih wj:s+ +,b33kh1eprimary is 100 A, we can expect the output current at the secondary to be

参考答案:    

标记此题
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 seco3j++r cfqoag232; fcpdfm+ km ndary has 200 turns. If the input voltcq3gpf23mko++adf+2m rf; cjage to the primary is 100 V, we can expect the output voltage of the secondary to be

参考答案:    

标记此题
86#
 
单选题 ( 1.0 分) 切至整卷模式 搜藏此题  
  The primary of a transformer has0i3xjhn15ohs2g il x; 100 turns and its secondary has 200 turns. If the power inpu1h2n jh30lxgoxi s 5i;t to the primary is 100 W, we can expect the power output of the secondary to be (neglecting frictional losses)

参考答案:    

标记此题
87#
 
单选题 ( 1.0 分) 切至整卷模式 搜藏此题  
  A generator produces 601xa h3ij pjg2,9da2e9gb4zaw A of current at 120 V. The voltage is usually stepped up to 4500 V by a transformer and transmitted through a power line of total resistance 1.0 W. Find the number of turns in the secondary if t ,bjpag2ax4hw e12a9ijd9 z g3he primary has 200 turns.

参考答案:    

标记此题
88#
 
单选题 ( 1.0 分) 切至整卷模式 搜藏此题  
  A generator produces 60 A of curb a .cfogmzy k; 8qhfxv3c95,)rent at 120 V. The voltage is usually stepped up to 4500 V by a transformer and transmitted through a power line og3bqyc9o f;hf v )cz8,.5kamxf total resistance 1.0 W. Find the percentage power lost in the transmission line.

参考答案:    

标记此题
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 lgm6mpqr9q 4o(z (qk9 V. The voltage is usually stepped up to 4500 V by a transformer and transmitted through a power line of totalq96(z9kmqor (l4p gqm resistance 1.0 W. Find the percentage power lost in the transmission line if the voltage is not stepped up.

参考答案:    

标记此题
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 3(v xm3yu e+q* 8z+lvqlel ,rctotal resistance of 0.60 W. A generator produces 100 V at 70 A. In order to reduce enu+(8*+mxqr zyve vql3lc ,l3e ergy 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 be lost if the transformer were not used?

参考答案:    

标记此题
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 resistancs53y)(4ayg gv -(x b uzn0ddcxe 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 y5ayx- nxz(gddb vu)c 3s04g(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?

参考答案:    

标记此题
92#
 
单选题 ( 1.0 分) 切至整卷模式 搜藏此题  
  100 kW is transmitted down a 6-W line at 1000 V. How much less power+;d0 k pvtr;nc would be lost if the power were +;;dcpkn 0rvttransmitted at 3000 V instead of at 1000 V?

参考答案:    

标记此题
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 45jli4)*b rz au mon6ia line with resistance of 0.60 W. To what voltage must the generator output be stepped up with a transii )mjulzoa6 *bn454r former if the power loss in transmission is not to exceed 0.010% of the original power?

参考答案:    

标记此题
94#
 
单选题 ( 1.0 分) 切至整卷模式 搜藏此题  
  A 4.0-mH coil carries a current of 5.0 A. How much energy is stored in th .xy,**q sg,d6wl pqvfe coil's magnetic field?wd6psg yl,.* v*x f,qq

参考答案:    

标记此题
95#
 
单选题 ( 1.0 分) 切至整卷模式 搜藏此题  
  A simple RL circuit contains a 6.0-W resistor and an of6epmyv:o-y7gtu:. h1jow5 18-H inductor. What is this circuitf6oph1 o7ejmw.yv5 g- u:toy:'s time constant?

参考答案:    

标记此题
96#
 
单选题 ( 1.0 分) 切至整卷模式 搜藏此题  
  What is the peak voltage in gm7 ta;0ocfo*an AC circuit where the rms voltage is 120 V?

参考答案:    

标记此题
97#
 
单选题 ( 1.0 分) 切至整卷模式 搜藏此题  
  A 150-W lamp is placed into a9mtpp2 ba.9q)dytq5wsets 4 * 120-V AC outlet. What is the peak current?

参考答案:    

标记此题
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 ACop95dxmt ,2f+ xvgekb t q2z4, outlet. What is the resistance of the lamqt k, g,tb+9x e5df2 zxm2v4opp?

参考答案:    

标记此题
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-V ac power supply. Whahuyi-y7f9 yfm.j6 fg4t is the peak curre g mu.7y4jy y9if-ffh6nt through the resistor?

参考答案:    

标记此题
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 p19pwxzm 4cpf0 ower diss0x1wp9pfm z 4cipated in the resistor?

参考答案:    

标记此题
101#
 
单选题 ( 1.0 分) 切至整卷模式 搜藏此题  
  The current through a 50-W resistor i26xeam p 6n5ybrd r.y jc.mda)ks 1,5ds $I = 0.80 \sin (240 t)$. What is the rms current?

参考答案:    

标记此题
102#
 
单选题 ( 1.0 分) 切至整卷模式 搜藏此题  
  The current through a 50-W resistor9jq( ( bllmb5iv:kv4c is $I = 0.80 \sin (240 t)$. At what frequency does the current vary?

参考答案:    

标记此题
103#
 
单选题 ( 1.0 分) 切至整卷模式 搜藏此题  
  The current through a 50ulv2a 6x9p v3f-W resistor is $I = 0.80 \sin (240 t)$. How much power on average is dissipated in the resistor?

参考答案:    

标记此题
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 i,(y: :-b3.hpj 8fu4 kyblb-beyms cqwnductor at 60 Hz?

参考答案:    

标记此题
105#
 
单选题 ( 1.0 分) 切至整卷模式 搜藏此题  
  What is the inductive reactance aidwzptgvv*--5 z8m0towu +*of a 2.50-mH coil at 1000 Hz?

参考答案:    

标记此题
106#
 
单选题 ( 1.0 分) 切至整卷模式 搜藏此题  
  At what frequency will a 14.tcz9o,wv.ko4 0-mH coil have 14.0 W of inductive reactance?

参考答案:    

标记此题
107#
 
单选题 ( 1.0 分) 切至整卷模式 搜藏此题  
  What inductance is necw .th +1/j 5tx75f3nq;- empnq fm hic5tyyzg0essary for 157 W of inductive reactance at 1000 Hz?

参考答案:    

标记此题
108#
 
单选题 ( 1.0 分) 切至整卷模式 搜藏此题  
  What current flows i toz0*n8,qlovn a 60-mH inductor when 120 V AC at a frequency of 20 kHz is applied to08nl,* oqzvto it?

参考答案:    

标记此题
109#
 
单选题 ( 1.0 分) 切至整卷模式 搜藏此题  
  What is the current through p4s)h:b9i iyja 2.50-mH coil due to a 110-V, 60.0 Hz source?

参考答案:    

标记此题
110#
 
单选题 ( 1.0 分) 切至整卷模式 搜藏此题  
  What is the capacitir +;7ug)/ 4eoh-mxlvvi3kxih ve reactance of a 4.7-mF capacitor at 10 kHz?

参考答案:    

标记此题
111#
 
单选题 ( 1.0 分) 切至整卷模式 搜藏此题  
  What size capacitor is needed to u:y ro ueuh-2/ud 6w:-r-objuhave 50 W of capacitive reactance at 10 kHz?

参考答案:    

标记此题
112#
 
单选题 ( 1.0 分) 切至整卷模式 搜藏此题  
  At what frequency does a 10-mF capacitod ;hu 6q*ucfgvt/rc8) r have a reactance of 1200 W?

参考答案:    

标记此题
113#
 
单选题 ( 1.0 分) 切至整卷模式 搜藏此题  
  At what frequency will the capacitive re:zx bvzfn7t+t6qtv ,j8 ml+e ,actance of a 0.010-mF capacitor be 100 W?tzvx+t :m6f lb7jtqv8,e n,z+

参考答案:    

标记此题
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+k ziz;5y) q;3kx vhur.0 V?

参考答案:    

标记此题
115#
 
单选题 ( 1.0 分) 切至整卷模式 搜藏此题  
  What is the impedance of an ac s,-t5mf5k++-zs o)r dezvbx k,qf7vv yeries circuit with 12.0 W resistance, 15.0 W inductive reactance, and 10.0 W capacitive reactszkb,f7qy5o)+-v,f+r5kz d tx ve- v mance?

参考答案:    

标记此题
116#
 
单选题 ( 1.0 分) 切至整卷模式 搜藏此题  
  What is the total impedance av8vs 23isrx/)baft )1iqug hovpi.7(t 1500 Hz if a 100-W resistor, 20-mH coil, and 1.0-mF capacitor are crsx/i (u32ps v f)aqhi8). otgv7bi1vonnected in series?

参考答案:    

标记此题
117#
 
单选题 ( 1.0 分) 切至整卷模式 搜藏此题  
  What is the phase angle at 1500 Hzcwwmbs 7(vm)wd-q1o a542/d; wmssfdr4 /uru if a 100-W resistor, 20-mH coil, and 1.0-mF capacitu1 dm;wqo c(bsd4 wwdrmaf2mw7/ /)rs4v-s5 uor are connected in series?

参考答案:    

标记此题
118#
 
单选题 ( 1.0 分) 切至整卷模式 搜藏此题  
  If a 1000-W resistor is s, 6s:po0lu4aauhaprcn,-m3 u tm9h7 connected in series with a 20-mH inductor, what is the impcu ,ta s-amu u7pas4rl,0h m 93hp:no6edance at 1000 Hz?

参考答案:    

标记此题
119#
 
单选题 ( 1.0 分) 切至整卷模式 搜藏此题  
  If a 1000-W resistor is connek *vfve2eq(y 9cted in series with a 20-mH inductor, what is the phase aqye *vvk 9fe(2ngle at 1000 Hz?

参考答案:    

标记此题
120#
 
单选题 ( 1.0 分) 切至整卷模式 搜藏此题  
  What resistance is needed in a series c;zuyquj685krm(a h22b -hdl t7+ yfcjircuit with a 20-mH coil and 1.0-mF capacitor for a total impedance of 100 2m b( hlqtc+y;d5ajzy-h rufk26u87j W at 1500 Hz?

参考答案:    

标记此题
121#
 
单选题 ( 1.0 分) 切至整卷模式 搜藏此题  
  Which of the following capacitances is e 1:xhil t, po1bj-0jhneeded in series with a 100-W resistor and 15-mH coil to gx0tjho:hi1 be 1j-,lpet a total impedance of 110 W at 2000 Hz?

参考答案:    

标记此题
122#
 
单选题 ( 1.0 分) 切至整卷模式 搜藏此题  
  What resistance must b 4 oz1zrel ed5py/b0b*e put in series with a 450-mH inductor at 5000 Hz for a to/y51eb*lez d4 p0zo brtal impedance of 40000 W?

参考答案:    

标记此题
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 ,aavpe+ t-j9 t zduych(o1q0 +at 1.0-MHz for a total impedan9jqtae hv+p1,tyac-(uo0z d +ce of 150 kW?

参考答案:    

标记此题
124#
 
单选题 ( 1.0 分) 切至整卷模式 搜藏此题  
  A 10-W resistor is connected in series with a 20-mF capacitor. What is the impo4e bwm nz;1(wedawbz4e ;mn 1wo(nce at 1000 Hz?

参考答案:    

标记此题
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-mF26l4t3s lwj7co sql z3,)aonx capacitor at 1.0 kHz for a total impedance of 45 W?) 4jot2wll c on 6s3,qszl7a3x

参考答案:    

标记此题
126#
 
单选题 ( 1.0 分) 切至整卷模式 搜藏此题  
  What resistance is needed in series with a 10-mF capacitor at 1.0 kHz for adr8t, ou iong./0av 4 cd16xxd phaseu t/6d8v.o4dx o,i 01adg crnx angle of $40^{\circ}$?

参考答案:    

标记此题
127#
 
单选题 ( 1.0 分) 切至整卷模式 搜藏此题  
  What capacitance is needed in series wr4cpl p9+;ufnxa : cb5ith a 30-W resistor at 1.0 kHz for a total impedance oap9pxnb fcr:+ ;lcu45f 45 W?

参考答案:    

标记此题
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 nc xxw zg,h9qx0cqt/ho r-7(+a 100-mF capacitor at 120 Hz. What is the phase angle?xc n0,hhtzx ocrx q 79q-gw(+/

参考答案:    

标记此题
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 co+o /a4zulze7p il, and 1.0-mF capacitor are connecte+euzoz47 /lpa d in series?

参考答案:    

标记此题
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 capacitohj9g1 xz7 unz6p.xd71udpn8 or, and a 0.350-H inductor. The circuit is connected to a 120-V, 60-Hz power supply. What is thedo177 6z 1gxj9pndh8uu. zpnx rms current in the circuit?

参考答案:    

标记此题
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 ckt *4*/ svl /9tijhq6js /qeyhapacitive reactance 30 W, and an inductor of inductive reactance 30 W are connej * /t tlqjqhe9/yk*ih4s6/vscted in series to a 110-V, 60-Hz power source. What current flows in this circuit?

参考答案:    

标记此题
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 ct 2b ih-c;x.v uwuxw:/ircuit containing a 50-W resistor, a 10-mF capacitor, and a ch 2 xi-x;u/twwbu.:v0.45-H inductor, when connected to a 60-Hz power supply?

参考答案:    

标记此题
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 5p0p *v7 l0 kfw(ghhgv h(u9fl900-W resistor for a phase angle o7l0lp9(pfv gf9gh(hv w 0k uh*f $40^{\circ}$ at 10 kHz?

参考答案:    

标记此题
134#
 
单选题 ( 1.0 分) 切至整卷模式 搜藏此题  
  A series RLC circuit has 8-r(3 jv26-wnz cs2ejo rlgcpR = 20.0 W, L = 200-mH, C = 10.0 mF. At what frequency should the circuit be driven in order to have maximum power transferred from th2-on3 ccp6- (zsr2e wvgj8r jle driving source?

参考答案:    

标记此题
135#
 
单选题 ( 1.0 分) 切至整卷模式 搜藏此题  
  What is the power output in ang8pcm4j* ged; ac series circuit with 12.0 W resistance, 15.0 W inductive reactance, and 10.0 W capacitive reactance, when the circuit is connected to a cpgg 4 ;d8emj*120-V power supply?

参考答案:    

标记此题
136#
 
单选题 ( 1.0 分) 切至整卷模式 搜藏此题  
  The phase angle of an Aiesoz)tr( z-hc:*4xv C circuit is $63^{\circ}$. What is the power factor?

参考答案:    

标记此题
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 W7.tv5j(jfd 2ya5kke(f7 y jj z. What is the poy.j df(a5tk7jyje5k7z2 v(f jwer factor?

参考答案:    

标记此题
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 conl15g(i /.iw6fh/,i aserly titaining a 50-W resistor, a 10-mF capacitor, and a 0.45-H inductor, whentl.hi6ag f/, wys5/rii 1ei(l connected to a 60-Hz power supply?

参考答案:    

标记此题
139#
 
单选题 ( 1.0 分) 切至整卷模式 搜藏此题  
  What is the resonant frequeoj tytz1rfok.19a4yfbty+vw 1 u;.o8 ncy of a 1.0-mF capacitor and a 15-mH coil in series?;t9o+.1jf 1rftbyy1oo vzau.y 8k4tw

参考答案:    

标记此题
140#
 
单选题 ( 1.0 分) 切至整卷模式 搜藏此题  
  What inductance is needed in series wit.vu5og3m e rs5h a 4.7-mF capacitor for a resonant frequeng.veo3 s um55rcy of 10 kHz?

参考答案:    

标记此题
141#
 
单选题 ( 1.0 分) 切至整卷模式 搜藏此题  
  What capacitance is needed in series with a 3/rkpdz+7bg 4-fxx a q7.7-mH inductor for a resonant frequency o+xxqd-7r4k / agp fb7zf 1000 Hz?

参考答案:    

标记此题
142#
 
单选题 ( 1.0 分) 切至整卷模式 搜藏此题  
  What size capacitor must be placed in ( td9 /6yok6+t zjnqie )xmq1lseries with a 30-W resistor and a 40-mH coid)6 jn (e6i+kqx /zml y1oqt9tl if the resonant frequency of the circuit is to be 1000 Hz?

参考答案:    

  • :
  • 总分:142分 及格:85.2分 时间:不限时
    未答题: 已答题:0 答错题:
    当前第 题,此次习题练习共有 142 道题
    本系统支持习题练习,作业与考试三大模式,作业考试自动评分,成绩排序一键导出,可设定动态变量同一试卷千人千题
    如果您对本系统感兴趣,想加入我们或者想进行任何形式的合作,请加微信 skysky1258

    浏览记录|手机版首页|使用帮助|题库网 (https://tiku.one)

    GMT+8, 2025-7-8 15:38 , Processed in 0.795373 second(s), 305 queries , Redis On.