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 ucotpxgv0:. 2b nits 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 sty v9fx; v.qph7-pj ss nhaj723p wq43vates 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 :vh;o */;1kfmmfvjzzw7d -az+ 7qjvy in a coil produces what kind of change on the inda wzm+1d :*fqfkzjv v-y;hj/7;7mzovuced $emf$, 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 field throu s.x0 (di-+davhg vc(93 kagabgh a loop of wire produces what kind of change o-gcdi3h0va(g bs+9ka.x(v a dn the induced $emf$, 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 produces whc* c o ;j6nzcwm.q,(ftr5d7ar; ugw 7pat kind of change on the induce;ofc.qp;7 um gj6 w twdcn,a7r(z*rc5d $emf$, 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 magrxeh yws4v: 4,;i e,kl;wob9znetic 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 an induced current in a conduct8 .pgj; d*4ry,c19rt:tab5 w fgo1fppke z4qmor will be that which tends to produce which ofk;adcjrmqypwf t15be fp: pz4ro9gt*4, 8g. 1 the following 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 hwslopad ,w8 y+)ldj(3vs,3dx;s. cr xeld above its center with its north pole pointing down. The stationary magnet induces y)+ddl3,3lcpwrsx s dsj ,(a; wv.o8x(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 arx dg)7 3q.zys;p0ebp horizontal table. A bar magnet is held above its center with its north pole pointing down, an 7qe d0r py;x3b).spzgd 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 where the magnetic field vector; 4maulnmp++fs(ggc0 ch/ 9i z points straight up. The magnetic field vanishes suddenly. When viewed from above, what is the ;nh0cgpmf+l94scm z/gai( +u 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 whe +mvgk 394cbzqb+fop/re the magnetic field vector points straight up. The m mvqb+c +3/pbg fo9kz4agnetic field suddenly grows stronger. When viewed from above, what is the direction of the induced current in this coil as the field increases?

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 in a region where the magneti i2 8reukt8 gmy-wg758plrt0zc field points s8t7g el wrzgi-p8um0rt k258 ytraight down. The magnetic field disappears suddenly. When viewed from above, what is the direction of the induced current in 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 3h mu5 bchk+0asq6pc(on a horizontal table and carries an ever-increasing current northward. Two coils of wire lie6ksm3h0p bcu cq5 h+(a flat on the table, one on either side of the 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 wi*lcwybj7+l(b re with the north pole entering first. As the north pole ent7b c*lyb+ ljw(ers 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 constant anguljn8fpbyorrz qlz.x:)ilm, ( :th/27p ar speed about an axis whose direction can be varied. In a region whz,lfpz h.)prln x:/q2 y7rm o b8ij:(tere 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?

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 angular speed av hf5 h t,:-kf6 ,cryq8vjmwp.bout an axis whose direction can be varied. In a region where a uniform magnetic field points straight down, what must be thfhw,hp q.:8 c 5f6vr-,jymtkve 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.8cegd5hh u:2tyo5l( l44 lhnw
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 aiv9 1 x9hz1f,/h gzdcan $emf$ 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 magnetic field+l(0ffx(* lf g4u,efw -mfsjp. 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 direction) is mov.sq4 le3hrfo6+ngk n6ed northward at constant velocity through a magnetic field that points straight down. Make a statement concerning the potential il6okq+46e ng fn hr3s.nduced 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 constant angular058 5qx 2wvpovlv5jy p 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 tg;z,gpc:vv vj6p4p v/ransforms

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 each second. The f7.w )g7 zgmfccrequency of th7)z7wfg c.gmc 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 p)j,6x6g h032bi w6u hpfcvwbto

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 devg sv;7myr-fz, ; qk,,t rb-ozuice that

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 seconj+c ;fa/wnfi,m(fuc )dary coil contains more loops than the primary coil )w,niffcj;c+/m(a f u then it is 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 coil contains more loolg3 9k(tf;b2m8s c6nc cc ;prgps than the secondary coil l;6cncccg m ;f392 bp (8gtskrthen 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 power inofbuykc ,4; ;z usa(i5put

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 circui tbltze s;( yaikp:/9(t,

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 batteyf )vnc r(/;csc0z r;dry of constant terminal voltage. At tsr)yc0r vfd z;c;cn(/he 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 induz:)j ctuvm6y5ctor are connected in series to an ideal battery of constant terminal voltage. At the moment contact is made with the battery, the voltage across the inductor isjc vz t:um)y65

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 withx elb:e/:as 4p inductance L and resistance R is connected to an $emf$. After a period of time, the current reaches a final value of 2.0 A. A second series circuit is identical except that the inductance is 2L. When it is connected to the same $emf$, what will be the final value of the current?

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 av.auazrb9 /.f nd 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?

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 inductor are connected in xwsorm1n 6l)*8gcm 5 -a5hgjmseries to a battery. The time constant for the circuit rerg m)-sj o x am65h*1m58gnclwpresents the time required 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 inductor are c3 xde2z p8wx:rwyj :+:i hx0qjonnected 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 currenwq: e0x prdz8+i3:xywhxj:j 2 t 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 units e x m.uemv(xd mo5x-419zbe7t 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 su 0j9p u/u6 ook4d)laedb ,bh,tpply. On 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 supztvo 99nhfhx4jupu; wq ;w -(7ply. In this circuit, the currentx97qh9-hfp;z4u( jo wvnw; ut

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 chu869 jns a6erf 0gsqo-anges by what factor when the frequency 06renssfa u986qog-jis 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 asr8.8jhe.tjm -guve s sh)vef 5m 7f9/cross an inductor is doubled, the inductive reactance o8vm8s .s tm)f9/e.efhj geuvhsr5-j7f that 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 a ,:*6 a:rerf5hu gmqg ocu e+2vk1uty7cross an inductor approaches zero, the inductive reac2g:,e u*:vc u htyfrae765oumq gkr+1tance of that coil

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 power supply. In t up g)jr/gc95uhis circuit, the curre cpg)9u/guj r5nt

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 circuit changes by what factor when f z)al62n9sqn the frequency is tripledfl)qn 269nz sa?

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, the 1buj( l6deka32q-m un oyqi f-1 sa+3pcapacdm bs6j n2oq f3a+1e(ul q1pa 3iu--kyitive reactance of that 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 volm:: mz wdz9,ivtages of the inductor and capacitor in a wdm z ,:zmi9:vRLC series 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 e rvj wz qf(98g4uo-,bc9la.ran RLC circuit is defined 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 impedance of the citv,3f-nq(5bc d7i-vze wa7egrcuit increases if R increases. Whe 5- en7f(7vdzc3 gvawib-qte,n is this 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. The impedance of the circuit increayty cl1wg8tmzmm3z167y 79ovy 4f a1ases 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 increases i 6j4,2+ sfkalpmfy df5dr)25soype 4yf $X_C$ 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 the capacitance both double in an1frd3kf 7l-vt.y2 zd h LRC series circuit, the k31fd- vf7d2yl rt z.hresonant frequency of 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 circuit that is driven by a0zc(hkegtog0kirxvc /9 67 z4n 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 cir lmo; -3kpgqn: x4-zwqcuit occurs 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 radius 0.10 m is rota lyyx46j.+0r0r2j fm/wtvszsy0lg3 hting in a uniform magnetic field of 0.20 T. Find the magnetic flux through the loop w s+j03 0 f4wlz/6mrgrysj h2lt.x0y yvhen 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 rotating in a uniforw65 (y zk3fh48 mt ypsb0qbem;m magnetic field of 0.20 T. Find the magnetic flux through the loop when the plane of the loop and the magnetic fi5fs m0 y(qt8e6kp ;mz3h 4wybbeld vector 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 06xp44rp m uyz4.10 m is rotating in a uniform magnetic field of 0.20 T. Find the magpz4rm up4yx64 netic flux through the loop when the plane of the loop and the magnetic field vector are at 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 sin29qj mo,*u h.t:rn/ g pk j9(shvjkc0-vyqr.pgle 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 changes fromt2c xk2t9y *k8vogl* u $4.0 \times 10^{-5} \; Wb$ 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 /nwm wn3g0cb,*ffbd- wire on a square frame with sides 18 cm. A uniform magnetic field is applied perpendicular to the plane of the coil. If the g 0wnff,3c * bnw-bm/dfield 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 with oke+teevn 47n3e9 tmn-s nva*5 dlwj71mk2 -q 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 anmdnkaroscx ak *..; 65p7e9zld area $0.20 \; m^{2}$ is placed with its axis parallel to a magnetic field of 0.40 T. The magnetic field changes from 0.40 T in the x-direction to 0.40 T in the negative x-direction in 2.0 s. If the resistance of the coil is 16 W, at what rate is power generated in the coil?

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 horizontally at a locn,rck)v28geq )zn b g;e)/xujb g0(diation where the downebjc(g/ rd eqz2n8;, u))0bvxggk )inward 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 at a constant angular velo.s uwczo 8) nr) y yelb06:udnv6nye66city of 2.0 rad/s about 0y6dlsy:6wu.)o nu yv b 68z6enrn)eca vertical axis through one of its ends while in a constant magnetic field of $5.0 \times 10^{-5} \; T$. If the magnetic field vector points straight down, what $emf$ is induced between the two ends of the bar?

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 has 50 loops anihn1dv rh9pikog:9 : +ok p,-zd 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 wire of ares :9rr+n9tbidwnz g7blc9g(w f;qp5-a $0.090 \; m^{2}$ 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 rectangular loops on its armature. Each loop is 12 c7qg3) teybbf 0m long and 8 cm wide. The armature rotates at 1200 rpm about an axis parallel t7e bbq0fgy)3to 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?

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 of 100 tuc2ev g:c.d- zarns 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 si6*maykl 8yy2axtz5 otnp1 z; 7mple AC generator with an output of 12 V maximlz6t p8o; z7m2yt *yakya 5xn1um when rotated 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?

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 maximum /77 g+:h3u +rjzfd(povu eu vz$emf$ 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 motor have a resistance of 6.00 W. The motor operate yau8/-zx-rn os 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. The motor operates on53p+d mog.5 *ez) 3k avtiopor 120 V AC, and when running at full speed it generates a bactp5i rpkeo.mov3+o d3gaz) *5k $emf$ 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 connectgtfrzoex8 )qf)x(1 .m ed to a 24-V power supply. The operat.18x rxfe)f mot)z (qging 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 resistancel y-ecr-e;:)c yk mjlba,j.cwly)k 0 p9z4ve( 6.0 W is connected to a 24-V power supply. The operating current is 1.0 A at full spyy0-;v,aem9jezrel (cbkj):c lw l-c. yp4 )keed. 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 resistance 6.0 W is connected to a 24-V power o8kw. s2qtov qk;v/1. 8yfdo,1sf wpcsupply. The2.wf1s8 os/kf18oq c.v o;twv dpy,qk operating 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 neof rc oevr6/0ye8 4(ymeded 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 flow in the seconpaxr6fohj37ve 64 n 0ndary. How many turns are in the 60hnnevjf47or3 a xp6 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 nece,rvihp c b4c22ssary in a 110-V primary if the 24-V secondary2p2, cc 4hvbir 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 consists of a 500-turnpawj 9,)rt6qg primary coil and a 2000-turn secondary coil. If the current in the secondary is 3.0 A 9 p,wjqgr6)at, what is the current 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 the primary of a transformer. Assuming 100% ei7p/8vhjci +a/a hm4+ um/gtdfficiency, how many amps at 24 V can flow in ti8ha7ahuigdc/v p4+ mtj/ m+/ he 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 transfo(iq i 82ca(adl;lu 7furmer provides 7500 V at 10.0 mA. The primar2dl ua;8u ii(caq 7(lfy coil operates on 120 V. What 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 ito. g: l;;o)x;m y*hdyajrf, mvk/ddn5s primary coil and 300 turns on its secondary coil. I;n.*d5 y/ f)okvo j,dxlrmd;myg : a;hf 120 V at 2.0 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 300 turns on it7;z p- jkgsma +v-jm8ts secondary coil. If 120 V at 2.0 A is applied to the primary, what curmkvj8j+zp g;- t-m as7rent 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 transformer has zg4*zq 96xb83yat j s4 iwc)ma100 turns and its secondary has 200 turns. If 8gay3smbtzjq 4i*)a 49 xzwc6the input current at the primary 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 secondary has 200 txj y1-do5l k.iurns. If the input voltage 1dox5l-.iyk jto 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 has 100 tn5vp(nmo e .1uurns and its secondary has 200 turns. If the power input to the primary is 100 W, we can expect the power m.vu1nn p5o( eoutput 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 60 A of current at 120 V. The voltage is usually stp: *lc bknvj)0epped 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 pr n:)jlv pk0*cbimary 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 current bjc-uybi,+ 5jzwa bnvp x7axt6 :0;u/at 120 V. The voltage is usually stepped up to 4500 V by a transformer and transmitted through a powerau/;y zjw 0b76c-b t:pvu5ia,njbx+x line of 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 V. The voltage is usually steu+rkdz bop, 4*6bqyw. pped up to 4500 V by a transformer and transmitted through a power line of total resistan+ko rq u64dyw*pb,.bzce 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 totamfv k;x0ns1 d1l 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 sm;0xv kd11fnturns 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 resistance of 0.6x c yq(knim4-,;p,iau0 W. A generator produces 100 Vkun i;c-x(p,yq4i ma , at 70 A. In order to reduce energy loss due to heating of the transmission line, the voltage is stepped up with a transformer with a turns ratio of 100:1. What percentage of the original energy is lost when the 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. sh y3z3dh*b4vgc: u 3n How much less power would be losdn33zh3c*h4s :gvb uyt if the power were transmitted 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 transmitfxf;nz 9a -iq(ted 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 x9;n fqiz a(f-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 the3 z9kgl;at3f tq i;v;h coil's magn9 kq; l3 ahz;vig3ftt;etic field?

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 contaik(lhe)iihu g)r8 :n (wns a 6.0-W resistor and an 18-H inductor. What is this circuit's time constawrkg(eu(ih)8 )nli :hnt?

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 an AC circuit where the8snv erg;h 0siw, pr8, 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 a 120-V AC outlet. atru*k1t:c8zmx l5l. 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-V3agvci;1 pf yee9yfd,p; z s ib,)nc8zs,hf(* AC outlet. What is the resistance of the lamp , z91*efs3dgi , n;y(,pzf) hbca8iycpef;v s?

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. Wha+ hwgn1 chg ae*+o-ax0t is the peak current through th n-g weoc+h*01gh+x aae 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 12i *pv/jeslsgnb8e msc-0 3ibki, i 08*+yi.dr0-V ac power supply. What is the power dissipatmg0li **,bsj0 i-.sebycsiv 8nik8/3pi +reded 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 resisx-bqwc .+b/oi tor is $I = 0.80 \sin (240 t)$. 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-Ws1 8nx7 fc9igh resistor 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 50-W resistorih38xhwudc*2k-: v3 odvarkkd rl ( ,0 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 inductor at 6cp44c /ucbt, xz 1;smp0 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 of a 2.50-mH coil at l1zl o27irv5g1000 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 14.0-9/z,wd amsfv8mH 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 necessary for g6 es7dfbdj42,s -ftt157 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 in a 60-mH inductor when 120 V AC at a frequency of 20 kH2ln9 q) ndkcabqnj t)y0i:,n1z is applied to it?lqnknyb ndj)nq:t c a,9i)20 1

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 a 2.50-mH coil due 6z90bsu ,i 1rda:s niuto 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 capacitive rear7isi+6osg2 b iwl6p:ctance 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 tu+i4rbus7 j +ao have 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 chdp7i dpx/q1ua6: q -fh19u ywapacitor 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 bpf786dp 7 l zhrap-g5reactance of a 0.010-mF capacitor be 100 W7l- 6 a75pz8hppfdgb r?

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 xn v7d.2hlz a1su2 wu)1000 Hz and 5.0 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 series circuit with 12.0 W resistance, 15.0 W s;en7l/ yhcp n :0*dxqinductive reactance, and 10.0 W capacitivey xq 7 nshc/p;l0*de:n reactance?

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 at 1500 Hz if a 100-W resisa3mbz:tg 50cmtta6u+9 cane 4 4+tltmtor, 20-mH coil, and 1.0-mF capacitor are cml 5 t t+atnm 9:b mzu34ccgt4t6+0aeaonnected 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 Hz if a 100-W resistor, 20-mH coil, and 1.02bt:xw-k fk:u6 l/k3n5d o lxz-mF capacitor are connectdk/:u f: xzx35-okk 2ln wl6bted 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 connected in series with a 20-mH i.4cp/mgs3 rxu navak ybp :/*;nductor, what is the impedanc n ;csvu/pr.p3axmkab *gy/:4e 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 connected in sem ,zpt3k3w)) x u ai0y/1kanckries with a 20-mH inductor, what is the phase angle at 10i)akcu3 z,y3 0xp atnk/1m)kw 00 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 seriebq kodwl5o0p g3w-j 0/s circuit with a 20-mH coil and 1.0-mF capacpj log5d w0 w/3-kbo0qitor for a total impedance of 100 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 needed in series with a 10w22bz5rw; fgx.g hwm90-W resistor and 15-mH coil to get a total9b zgmgfh.x;ww 5 22wr 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 be put in series d3ho ch t .8uq+)wt/a.s rv6klwith a 450-mH inductor at 5000 Hz for a total impedance of 40000 Wql d6s3.+o)aw .hct hr/tk8 vu?

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 7*rrc1p5h h, jnr ho f4-y96df 8dwfddresistor at 1.0-MHz for a total imfrd5fd41n - rc, oy67*dhhd9hwpf8j rpedance 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 ser q:01fso9lbpej,v co h/; hwc0ies with a 20-mF capacitor. What is the impedance at 100pe:,qh;j fs/h90 bo 1cc lo0wv0 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 se1eo+aia zu -loi5*1.s dk.qo mries with a 10-mF capacitor at 1.0 kHz for a total impedance of 45amo.*. ou1e1zklio-id+ 5s q a W?

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 a ph5g53eu0 ct2f p8li*n4ifwu2la*eng ease angle ofgil05uwl485tff e g*p ni23unec2e*a $40^{\circ}$?

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 sers2hwvui6dfsja/ y 1 :ch9g9 3tk.f9xr5e1wwdies with a 30-W resistor at 1.0 kHz for a total i3 wag 5fi1fv2wxhk9s.h 9w1t c/rsuy:d69j edmpedance of 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 a 100-mF capacitor at 120 Hz. What is+epwz b452x5td a )vwg the phase td w v5eag4z+wpxb )25angle?

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 10o2ua mi. vzoprrp9p-qd )-s8 00-W resistor, 20-mH coil, and 1.0-mF capacitor are con)avoq9po2pr.s-ri80zudp -m nected 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 c pp(187xogv*pnny u:, urt- ;jbcrwo/onsists of a 100-W resistor, a 10.0-mF capacitor, and a 0.350-H inductorcyp 1r o r;7upju8*o-pnx:(/n ,v bwtg. The circuit is connected to a 120-V, 60-Hz power supply. What is the 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 capacitive reactance 30 W, . hob*o: 2rll4 zd-mbl. xd5raand an inductor of inductive reactance 30 W are connected in series to a 110-V, 60-Hz power source. What currentl ld a..2r:ro 5mhbblxz-*4o d 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 circuit containing a 50-W resist2:1o*n8th,e m qyhjc yor, a 10-mF capacitor, and a 0.45-H inductor, when connected to a 60-Hz power suppl *j,yyom8hcn ehqt: 12y?

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 necessarh(q (xj4q f,dfy in series with a 500-W resistor for a phase angle of ,fqj( (f4 xqdh$40^{\circ}$ 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 R = 20vn0ifpujd1 p/a.y4 0t h7d jo*0dmoc /.0 W, L = 200-mH, C = 10.0 mF. At what frequency should the circuit be driven in order to have maximum power tjo*pycmi tn 1 d0d f do70pv/j0/.u4ahransferred from the 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 an ac series circuit with 12.0 W resv: qt,1jw7eabistance, 15.0 W inductive reav:teb ,qa7 j1wctance, and 10.0 W capacitive reactance, when the circuit is connected to a 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 AC ci) bs o.(u7tqkgrcuit 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)(r ,ykshe1gz v2a 1zh of 60 W and a resistance of 30 W. What is the power factvzk1)rsz 1hh g2e y(a,or?

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 containing a 50-W resistor,65m)0jrgu sxe;p0xlr td+ tq 6 a 10-mF capacitor, and a 0.45-H indu+mxrr50x0s g q)6etdpuj6t;lctor, when 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 frequency of a 1.0-mF capacitor and a 15-mH coil in s71v4( oxze9;bn yx ryleries?xb1el9vnxo 7r(;y 4zy

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 with a 4.48r4 w+* qrb ejbns,4hovbrn(7-mF capacitor for a resonant frequenco+ 4eswhbr*8jn ,bqr v4b(4rny 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 3.7-mH inductor for a reson ( (a8b;hb,pb 4pfj7h swjkql/ant frequency (wjbf (j4pl8s ,qa;b7h /k bphof 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 6 l*/ asfgys*vmust be placed in series with a 30-W resistor and a 40-mH coil if the resonant frequency of the circuit is to be /s* asgf l6y*v1000 Hz?

参考答案:    

  • 答题人:
  • 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|使用帮助|手机版|切到手机版|题库网 (https://tiku.one)

    GMT+8, 2024-10-3 11:19 , Processed in 0.681658 second(s), 305 queries , Redis On.