Physics Unit23: Light and Geometric Optics - 51fly国际课程 (51fly.win)

1#

Reflection, refraction, and 547x(tjz;vun kuh/ tof2*bzm the formation of images by mirrors and lenses has been sucxv t*jzbh5z/f;nu7tm2 u( o 4kcessful described by the

A. wave model of light.

B. ray model of light.

C. particle model of light.

D. none of the given answers

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2#

单选题 ( 1.0 分) 切至整卷模式搜藏此题

The angle of incidenc*ng(gj wn *unlgdl675e

A. must equal the angle of reflection.

B. is always less than the angle of reflection.

C. is always greater than the angle of reflection.

D. may be greater than, less than, or equal to the angle of reflection.

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3#

单选题 ( 1.0 分) 切至整卷模式搜藏此题

The principle on which mirrors wore7jzd6pe(2bj *s 3kow af5hn6k is

A. refraction.

B. polarization.

C. dispersion.

D. reflection.

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4#

单选题 ( 1.0 分) 切至整卷模式搜藏此题

A plane mirror forms an ilhv6 eqqvju; -kj4r)i0 12 vpimage that is

A. real and upright.

B. virtual and upright.

C. real and upside down.

D. virtual and upside down.

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5#

单选题 ( 1.0 分) 切至整卷模式搜藏此题

Plane mirrors produce m lv/ -vh1h6/oo +pkj 2dvr6ueimages which

A. are always smaller than the actual object.

B. are always larger than the actual object.

C. are always the same size as the actual object.

D. could be smaller, larger, or the same size as the actual object, depending on the placement of the object.

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6#

单选题 ( 1.0 分) 切至整卷模式搜藏此题

An image formed when the light rays do not actually pass through the imagev3z8a qms.(4ck3whhz location, and would not appear on pa zm(3chzwqas.3 8 4vkhper or film placed at that location is referred to as

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7#

单选题 ( 1.0 分) 切至整卷模式搜藏此题

An image formed when the light rays pass through the image uqoa5 nh,h4j;-( filklocation, and could appear on paper or film placed at theh; kifqjun(lo-a4h5, that location is referred to as

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8#

单选题 ( 1.0 分) 切至整卷模式搜藏此题

Is it possible to see a virtual im ;46 yie(6gsb;2e2nzk neqvcpage?

A. No, since the rays that seem to emanate from a virtual image do not in fact emanate from the image.

B. No, since virtual images do not really exist.

C. Yes, the rays that appear to emanate from a virtual image can be focused on the retina just like those from an illuminated object.

D. Yes, since almost everything we see is virtual because most things do not themselves give off light, but only reflect light coming from some other source.

E. Yes, but only indirectly in the sense that if the virtual image is formed on a sheet of photographic film, one could later look at the picture formed.

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9#

单选题 ( 1.0 分) 切至整卷模式搜藏此题

A spherical mirror on which reflection takes place on the outer surface of x*5 u q mw/uwq- x,1y1jx,sbwdthe spherical s j,/ 1uxm5wb* q ws-1yquxx,dwhape is referred to as a

A. convex mirror.

B. concave mirror.

C. plane mirror.

D. double-sided mirror.

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10#

单选题 ( 1.0 分) 切至整卷模式搜藏此题

A spherical mirror on which reflectiona)qm)x .2pfcs oy1j /j)hwlk( takes place on the inner surface of the sphere2oj1qc/psay kjw)). hf m lx)( is referred to as a

A. convex mirror.

B. concave mirror.

C. plane mirror.

D. double-sided mirror.

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11#

单选题 ( 1.0 分) 切至整卷模式搜藏此题

If the radius of curvature of the concave mirror is r, the w)rl4jjf7,mw1 ghz j4q7;trl focal length is

A. 2r

B. r

C. r/2

D. cannot be determined from the information given

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12#

单选题 ( 1.0 分) 切至整卷模式搜藏此题

A light ray, traveling parallel to a concave mirror's axi 3; l nk,rbme),xnvm:4f wpkx+s, strikes the mirror's surfaceb)+mvwmr,k: 4npxf3e nl, k;x near its midpoint. After reflection, this ray

A. again travels parallel to the mirror's axis.

B. travels at right angles to the mirror's axis.

C. passes through the mirror's center of curvature.

D. passes through the mirror's focal point.

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13#

单选题 ( 1.0 分) 切至整卷模式搜藏此题

Light arriving at a concave mirror ono.)z17:w p u rmfc ho3*op4ciz a path parallel to the axis is reflected

A. back parallel to the axis.

B. back on itself.

C. through the focal point.

D. through the center of curvature.

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14#

单选题 ( 1.0 分) 切至整卷模式搜藏此题

A light ray, travelin:,*fre dcv; h.oeg6ij g obliquely to a concave mirror's axis, crosses the axis at the mirror's center of curvature bergei,f dc;ov :jh*6.efore striking the mirror's surface. After reflection, this ray

A. travels parallel to the mirror's axis.

B. travels at right angles to the mirror's axis.

C. passes through the mirror's center of curvature.

D. passes through the mirror's focal point.

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15#

单选题 ( 1.0 分) 切至整卷模式搜藏此题

Light arriving at a concave mirror on a path throuf,2t7ila8 mj, r9i mvoc;l4h igh the center of curvature is ref ii2f a7 mljm t4vh8lo;rc,9,ilected

A. back parallel to the axis.

B. back on itself.

C. through the focal point.

D. midway between the focal point and the center of curvature.

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16#

单选题 ( 1.0 分) 切至整卷模式搜藏此题

A light ray, traveling obliquely to a concave mirror's surfa.m 7geylrustbsi0 -9s(hb1 j:ce, crosses the axis at the mirror's focal point before striking the mirror's surface. After res19 sb l e(utr7ih:.jy0sg-mb flection, this ray

A. travels parallel to the mirror's axis.

B. travels at right angles to the mirror's axis.

C. passes through the mirror's center of curvature.

D. passes through the mirror's focal point.

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17#

单选题 ( 1.0 分) 切至整卷模式搜藏此题

Light arriving at a concave mirror on a path through the focal point is refldsoj q)b/p4yz o3ks4*ectedp jzdqo4 )4b/oys*3ks

A. back parallel to the axis.

B. back on itself.

C. through the focal point.

D. through the center of curvature.

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18#

问答题 ( 1.0 分) 切至整卷模式搜藏此题

State how to draw the three rays for finding the image position2b7hu, ,) fwl;av+qt4xmi i nt due to a curved mirrm2u,fa)xt+n,tbi q4;h i v7wlor.

该题自我估分: (必填) (满分:1.0分)

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19#

单选题 ( 1.0 分) 切至整卷模式搜藏此题

If you stand in front of a concave mirror, exactly at i6bfp aig0ysa7+hqdy0cyf /q c -w0)n2ts focal point,

A. you won't see your image because there is none.

B. you won't see your image because it's focused at a different distance.

C. you will see your image, and you will appear smaller.

D. you will see your image and you will appear larger.

E. you will see your image at your same height.

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20#

单选题 ( 1.0 分) 切至整卷模式搜藏此题

An object is placed at a concave mirror' svd/ q994rldzs center of curvature. The image produced by ts/9d v 9q4zldrhe mirror is located

A. out beyond the center of curvature.

B. at the center of curvature.

C. between the center of curvature and the focal point.

D. at the focal point.

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21#

单选题 ( 1.0 分) 切至整卷模式搜藏此题

An object is positioned between a concave mirror's cent,5jc; oetvzgd,b x9 ,ser of curvature and its focal point. The image produced by the mirror isoc,,;exgj5 z, 9stdb v located

A. out past the center of curvature.

B. at the center of curvature.

C. between the center of curvature and the focal point.

D. at the focal point.

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22#

单选题 ( 1.0 分) 切至整卷模式搜藏此题

An object is situated between a concave mirror's surface and its focal ,/.fw- b;e1:o*awfwdfs lk otpoint. The image formed in fd*ok-so: 1w;blafew, ftw/.this case is

A. real and inverted.

B. real and erect.

C. virtual and erect.

D. virtual and inverted.

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23#

单选题 ( 1.0 分) 切至整卷模式搜藏此题

If you stand in front of a convex mirror, at the same distance fro1fv6.m g4iugbi (8klem it as its radius of cu4e1mkiui b68vf .l(g grvature,

A. you won't see your image because there is none.

B. you won't see your image because it's focused at a different distance.

C. you will see your image and you will appear smaller.

D. you will see your image and you will appear larger.

E. you will see your image at your same height.

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24#

单选题 ( 1.0 分) 切至整卷模式搜藏此题

If you stand in front of a con:6)f+a0k 8w r lpcxz,j0 e+g pvd2xacwvex mirror, at the same distance from it as its focal l ckcewarzj )0:8 g2v,wxd++alpxp6f0ength,

A. you won't see your image because there is none.

B. you won't see your image because it's focused at a different distance.

C. you will see your image and you will appear smaller.

D. you will see your image and you will appear larger.

E. you will see your image at your same height.

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25#

单选题 ( 1.0 分) 切至整卷模式搜藏此题

Sometimes when you look into a curd q-( wxli+;klp/ud9 fved mirror you see a magnified image (a great b/ d- k +;qwfl9ulpixd(ig you) and sometimes you see a diminished image (a little you). If you look at the bottom (convex) side of a shiny spoon, what will you see?

A. You won't see an image of yourself because no image will be formed.

B. You will see a little you, upside down.

C. You will see a little you, right side up.

D. You will see a little you, but whether you are right side up or upside down depends on how near you are to the spoon.

E. You will either see a little you or a great big you, depending on how near you are to the spoon.

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26#

单选题 ( 1.0 分) 切至整卷模式搜藏此题

Concave spherical mirrorscnf h :u.yxpd 7:;z.ci produce images which

A. are always smaller than the actual object.

B. are always larger than the actual object.

C. are always the same size as the actual object.

D. could be smaller than, larger than, or the same size as the actual object, depending on the placement of the object.

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27#

单选题 ( 1.0 分) 切至整卷模式搜藏此题

Convex spherical mirrors produce images w. y i:iawc.kz8hich

A. are always smaller than the actual object.

B. are always larger than the actual object.

C. are always the same size as the actual object.

D. could be larger than, smaller than, or the same size as the actual object, depending on the placement of the object.

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28#

单选题 ( 1.0 分) 切至整卷模式搜藏此题

A single concave spherical mirror produces an image w . m6/0 boel.;vly9uni unne1zhich is

A. always virtual.

B. always real.

C. real only if the object distance is less than $f$.

D. real only if the object distance is greater than $f$.

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29#

单选题 ( 1.0 分) 切至整卷模式搜藏此题

A single convex spherical mirror prou*(8 h.c,5e0sf s l nsefsx*wjduces an image which is

A. always virtual.

B. always real.

C. real only if the object distance is less than $f$.

D. real only if the object distance is greater than $f$.

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30#

单选题 ( 1.0 分) 切至整卷模式搜藏此题

A negative magnification for a mir+4 *clas0be8sd wb,zjror means

A. the image is inverted, and the mirror is concave.

B. the image is inverted, and the mirror is convex.

C. the image is inverted, and the mirror may be concave or convex.

D. the image is upright, and the mirror is convex.

E. the image is upright, and the mirror may be concave or convex.

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31#

单选题 ( 1.0 分) 切至整卷模式搜藏此题

If the image distance is po+ no0hyoo3- nbkmq +;isitive, the image formed is

A. a real image.

B. a virtual image.

C. either a real or virtual image.

D. can not be determined.

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32#

单选题 ( 1.0 分) 切至整卷模式搜藏此题

If the image distance ir ok10o1sm*4hub siun nm6 u5f8st .(rs negative, the image formed is

A. real image.

B. virtual image.

C. either a real or virtual image.

D. can not be determined.

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33#

单选题 ( 1.0 分) 切至整卷模式搜藏此题

If the magnification is t f7bbi 8tn34mk cwcar s7f2;:a positive value, the image is

A. upright.

B. inverted.

C. enlarged.

D. shrunk.

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34#

单选题 ( 1.0 分) 切至整卷模式搜藏此题

If the magnification is a negative value, the image im 5eh*f )rtrs)g+k/ pws

A. upright.

B. inverted.

C. enlarged.

D. shrunk.

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35#

单选题 ( 1.0 分) 切至整卷模式搜藏此题

If the absolute value of the magnification is larger than jdmv02 .-i ch/rikn+xone, then the image iskjxh0 vc d .i-+inm2r/

A. larger than the object.

B. the same size as the object.

C. smaller than the object.

D. can not be determined.

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36#

单选题 ( 1.0 分) 切至整卷模式搜藏此题

If the absolute value of the magnification is smallez -k- 6pkmvi*er than one, then the image isz* ek k-6mivp-

A. larger than the object.

B. the same size as the object.

C. smaller than the object.

D. can not be determined.

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37#

单选题 ( 1.0 分) 切至整卷模式搜藏此题

If the absolute value of t*h:lak15 lyn:0wayzvy z8nh 4 he magnification is equal to one, then the image is

A. larger than the object.

B. the same size as the object.

C. smaller than the object.

D. can not be determined.

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38#

单选题 ( 1.0 分) 切至整卷模式搜藏此题

Light travels fastes:rt:apvo7 r) et

A. in a vacuum.

B. through water.

C. through glass.

D. through diamond.

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39#

单选题 ( 1.0 分) 切至整卷模式搜藏此题

For all transparent material substances, the index t* ,wsv7c oihm * :rh66bnofa1of refraction

A. is less than 1.

B. is greater than 1.

C. is equal to 1.

D. could be any of the given answers as it all depends on optical density.

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40#

单选题 ( 1.0 分) 切至整卷模式搜藏此题

An index of refraction less than o*cr0 */gn4(xpn cwvfvne for a medium would imply

A. that the speed of light in the medium is the same as the speed of light in vacuum.

B. that the speed of light in the medium is greater than the speed of light in vacuum.

C. refraction is not possible.

D. reflection is not possible.

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41#

单选题 ( 1.0 分) 切至整卷模式搜藏此题

The index of refraction of diamond im j4twrt-dhn6x:+2 m ts $2.42$. This means that a given frequency of light travels

A. 2.42 times faster in air than it does in diamond.

B. 2.42 times faster in diamond than it does in air.

C. 2.42 times faster in vacuum than it does in diamond.

D. 2.42 times faster in diamond than it does in vacuum.

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42#

单选题 ( 1.0 分) 切至整卷模式搜藏此题

The angle of incidencehja zx.*01z9c4m co nw

A. must equal the angle of refraction.

B. is always less than the angle of refraction.

C. is always greater than the angle of refraction.

D. may be greater than, less than, or equal to the angle of refraction.

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43#

单选题 ( 1.0 分) 切至整卷模式搜藏此题

Light traveling at an angle into a denser ml,+ smgx27 a r:nrp*pzedium is refracted

A. toward the normal.

B. away from the normal.

C. parallel to the normal.

D. equally.

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44#

单选题 ( 1.0 分) 切至整卷模式搜藏此题

Light enters air from water. The angle of refraction will be0p+7llc:cch:i mkt(d 9.ak 4r6/s3fd kpdw ra

A. greater than the angle of incidence.

B. equal to the angle of incidence.

C. less than the angle of incidence.

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45#

单选题 ( 1.0 分) 切至整卷模式搜藏此题

A ray of light, which is traveling in -e3.k k.d- mvcwojd 1fair, is incident on a glass plate at a $45^{\circ}$ angle. The angle of refraction in the glass

A. is less than $45^{\circ}$.

B. is greater than $45^{\circ}$.

C. is equal to $45^{\circ}$.

D. could be any of the above; it all depends on the index of refraction of glass.

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46#

单选题 ( 1.0 分) 切至整卷模式搜藏此题

The principle on which fibe8:upd 3v v -p()yfbpkar optics is based is

A. refraction.

B. polarization.

C. dispersion.

D. total internal reflection.

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47#

单选题 ( 1.0 分) 切至整卷模式搜藏此题

The critical angle for a beamnel:lf cw x;(+ of light passing from water into air is $48.8^{\circ}$. This means that all light rays with an angle of incidence greater than this angle will be

A. absorbed.

B. totally reflected.

C. partially reflected and partially transmitted.

D. totally transmitted.

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48#

单选题 ( 1.0 分) 切至整卷模式搜藏此题

The principle on which lenseb qk/(b j60cpf *qo) bbn5t:pws work is

A. refraction.

B. polarization.

C. dispersion.

D. total internal reflection.

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49#

单选题 ( 1.0 分) 切至整卷模式搜藏此题

Lenses that are thickest atf tk)9ioods,c sbl j6iwv:*p l(p,4t, the center called

A. converging lenses.

B. diverging lenses.

C. either converging or diverging lens.

D. can not be determined.

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50#

单选题 ( 1.0 分) 切至整卷模式搜藏此题

Lenses that are thinner at t4iu-j,jv)zwb5 bde; z he center than the edges are called

A. converging lenses.

B. diverging lenses.

C. either converging or diverging lens.

D. can not be determined.

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51#

单选题 ( 1.0 分) 切至整卷模式搜藏此题

Lenses that are thicker at no(if3 ev.6 79pcpvlethe center

A. spread out light rays.

B. bend light rays to a point beyond the lens.

C. have no effect on light rays.

D. reflect light rays back.

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52#

单选题 ( 1.0 分) 切至整卷模式搜藏此题

Two diverging lenses arezpx;gm :*atdh6evfn) 7;e.g8iai 3nb similar except that lens B is rated at 20 diopters, whereas lens A is *ii6gb:np)gvzh.t;3adf7ex8am n ;e rated at 10 diopters. The focal length of lens B is

A. one-fourth of the focal length of lens A.

B. one-half of the focal length of lens A.

C. twice the focal length of lens A.

D. four times the focal length of lens A.

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53#

单选题 ( 1.0 分) 切至整卷模式搜藏此题

A light ray, traveling parallel to thev u;v9w0 9n0c+(gku ze 2jz f;6vuksq-.cucem axis of a thin concave lens, strikes the lens near its midpoinmfg0q(vjev s ;+zk6cv2nk9 ucceu; .z0 uw- u9t. After traveling though the lens, this ray emerges traveling obliquely to the axis of the lens

A. such that it never crosses the axis.

B. crossing the axis at a point equal to twice the focal length.

C. passing between the lens and its focal point.

D. passing through the focal point.

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54#

单选题 ( 1.0 分) 切至整卷模式搜藏此题

A light ray, traveling cm kzg, 8ovz6;6ygznt; a)2rrparallel to the axis of a convex thin lens, strikes the lens near its midpoint. After traveling through the lens, this ray emergegtrk mr;zz8c 6;2,)nz oavg6ys traveling obliquely to the axis of the lens

A. such that it never crosses the axis.

B. crossing the axis at a point equal to twice the focal length.

C. passing between the lens and its focal point.

D. passing through its focal point.

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55#

问答题 ( 1.0 分) 切至整卷模式搜藏此题

State how to draw the three rays for finding thahxxa mj .o:c*t.*(put-x;qz e image position due to a thin lemqh x(czo;a.:x*x p-*ju .tat ns.

该题自我估分: (必填) (满分:1.0分)

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56#

单选题 ( 1.0 分) 切至整卷模式搜藏此题

A convex lens has focal length 8 cnmpfsy(l2 18k qo; wbpc+/u$f$. An object is located at infinity. The image formed is located

A. at $2f$.

B. between $f$ and $2f$.

C. at $f$.

D. between the lens and $f$.

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57#

单选题 ( 1.0 分) 切至整卷模式搜藏此题

A convex lens has a foc3k0*y ifd ::yhkvw 0bgly* nck4wc-2mal length $f$. An object is placed at $f$ on the axis. The image formed is located

A. at infinity.

B. between $2f$ and infinity.

C. at $2f$.

D. between $f$ and $2f$.

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58#

单选题 ( 1.0 分) 切至整卷模式搜藏此题

A convex lens has a fo f j,w.9lnmk7hcal length $f$. An object is placed at $f$ on the axis. The image formed is located

A. at $2f$.

B. between $f$ and $2f$.

C. at $f$.

D. between the lens and $f$.

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59#

单选题 ( 1.0 分) 切至整卷模式搜藏此题

A convex lens has a focal jldl5mogk:w.yz )o8r9, *4ked z s6dclength $f$. An object is placed between $f$ and $2f$ on the axis. The image formed is located

A. at $2f$.

B. between $f$ and $2f$.

C. at $f$.

D. at a distance greater than $2f$ from the lens.

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60#

单选题 ( 1.0 分) 切至整卷模式搜藏此题

A convex lens has a focal lenwlhb y6-(p9gi *on e/7p zrrs:gth $f$. An object is placed between infinity and $2f$ from the lens on its axis. The image formed is located

A. at $2f$.

B. between $f$ and $2f$.

C. at $f$.

D. between the lens and $f$.

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61#

单选题 ( 1.0 分) 切至整卷模式搜藏此题

A object is placed between a convex lens and its focfq v8tw2h n;a3a6*vyufn:- aral point. The image formed i 8236 a*v-tynh ;a:rqvfufnwa s

A. virtual and erect.

B. virtual and inverted.

C. real and erect.

D. real and inverted.

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62#

单选题 ( 1.0 分) 切至整卷模式搜藏此题

The images formed by concave lense2vk.prpu l4(:p vyd p0s

A. are always real.

B. are always virtual.

C. could be real or virtual; it depends on whether the object distance is smaller or greater than the focal length.

D. could be real or virtual, but always real when the object is placed at the focal point.

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63#

单选题 ( 1.0 分) 切至整卷模式搜藏此题

The image of the rare stamp you s( *gbadu ;c8ozee through a magnifying glass is

A. always the same orientation as the stamp.

B. always upside-down compared to the stamp.

C. either the same orientation or upside-down, depending on how close the stamp is to the glass.

D. either the same orientation or upside-down, depending on the thickness of the glass used.

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64#

单选题 ( 1.0 分) 切至整卷模式搜藏此题

A lamp is placed 1 m from a sco 9f ft6jt1w9creen. Between the lamp and the screen is placed a converging lens of focal length 24 cm. The filament of the lajw9t1toff9 6c mp can be imaged on the screen. As the lens position is varied with respect to the lamp,

A. no sharp image will be seen for any lens position.

B. a sharp image will be seen when the lens is halfway between the lamp and the screen.

C. a sharp image will be seen when the lens is 40 cm from the lamp.

D. a sharp image will be seen when the lens is 60 cm from the lamp.

E. a sharp image will be seen when the lens is either 40 cm from the lamp or 60 cm from the lamp, but not otherwise.

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65#

单选题 ( 1.0 分) 切至整卷模式搜藏此题

Two thin lenses, of focal lengths 3 jxq05quike5 $f_1$ and $f_2$ placed in contact with each other are equivalent to a single lens of focal length of

A. $f_1 + f_2$.

B. $1/(f_1 + f_2)$.

C. $(f_1 + f_2)/f_1 f_2$.

D. $f_1 f_2/(f_1 + f_2)$.

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66#

单选题 ( 1.0 分) 切至整卷模式搜藏此题

Two thin double-convex (convex-convex) lenses are placed in contact. If each :i9xsr( h h)6zv9xugf has a focal length of 20 cm, how would you expect the combinatio9fsgx9i(zx6 )r h v:hun to function?

A. about like a single lens of focal length 20 cm

B. about like a single lens of focal length 40 cm

C. about like a single lens of focal length slightly greater than 20 cm

D. about like a single lens of focal length less than 20 cm

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67#

单选题 ( 1.0 分) 切至整卷模式搜藏此题

A diverging lens ($f = -4.0 \; cm$) is positioned 2.0 cm to the left of a converging lens ($f = +6.0 \; cm$). A 1.0-mm diameter beam of parallel light rays is incident on the diverging lens from the left. After leaving the converging lens, the outgoing rays

A. converge.

B. diverge.

C. form a parallel beam of diameter D > 1.0 mm.

D. form a parallel beam of diameter D < 1.0 mm.

E. will travel back toward the light source.

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68#

单选题 ( 1.0 分) 切至整卷模式搜藏此题

A laser beam strikes a plane's reflecting sundaiut..pd6:r/ yo 5krface with an angle of incidence of 6drid u/y.to n :5.akp$52^{\circ}$. What is the angle between the incident ray and the reflected ray?

A. $52^{\circ}$

B. $105^{\circ}$

C. $45^{\circ}$

D. $90^{\circ}$

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69#

单选题 ( 1.0 分) 切至整卷模式搜藏此题

An object is located 2.6 m in front of a plane mirror. The image formez jdca+q.x,4v j3 s e4lopsn, arb7cc u+;/qc:d by the mirror appears to +qa src4 x.j /3n,cjcb,+q 4 dlucz ae7v:p;sobe

A. 1.3 m in front of the mirror.

B. on the mirror's surface.

C. 1.3 m behind the mirror's surface.

D. 2.6 m behind the mirror's surface.

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70#

单选题 ( 1.0 分) 切至整卷模式搜藏此题

How far are you from your image when you stand 0.75 m in front of a ver3atc1c*v 4dnq tical plane mv *adq 41ccn3tirror?

A. $0.75 \; m$

B. $1.5 \; m$

C. $3.0 \; m$

D. none of the given answers

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71#

单选题 ( 1.0 分) 切至整卷模式搜藏此题

How fast do you approach your image when you approach a verti*rjq1q 8l bls0cal plane mirror at a speed of 2 m/s*jq 8 0blqlrs1?

A. 1 m/s

B. 2 m/s

C. 4 m/s

D. none of the given answers

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72#

单选题 ( 1.0 分) 切至整卷模式搜藏此题

A spherical concave mirror has a radius of curvature of 20 cm. How far freh-w 4y mpbl 4f3z(xz9om the mirror is the focal point located?e(fxz9wl4 h -3p4z myb

A. $10 \; cm$

B. $20 \; cm$

C. $30 \; cm$

D. $40 \; cm$

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73#

单选题 ( 1.0 分) 切至整卷模式搜藏此题

A concave mirror with a radius of 20 cm crbv44spi(p1 n ieates a real image 30 cm from the mirror. What is thipi14 n(pb4vse object distance?

A. $20 \; cm$

B. $15 \; cm$

C. $7.5 \; cm$

D. $5.0 \; cm$

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74#

单选题 ( 1.0 分) 切至整卷模式搜藏此题

A object is 12 cm in front of a concave mirror, and the image is l4nmh: o w:,cc3.0 cm in front of the mirhc:cw n, mo4l:ror. What is the focal length of the mirror?

A. $15 \; cm$

B. $4.0 \; cm$

C. $2.4 \; cm$

D. $1.3 \; cm$

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75#

单选题 ( 1.0 分) 切至整卷模式搜藏此题

An object is 10 cm in front of a concave m*d4oil+ hrb/r irror with focal length 3 cm. Where is the image? hid/+r* 4lrbo

A. 13 cm from the mirror

B. 7.0 cm from the mirror

C. 4.3 cm from the mirror

D. 3.3 cm from the mirror

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76#

单选题 ( 1.0 分) 切至整卷模式搜藏此题

A concave spherical mirror has a focal length of 20 cm. An object is place2 8 d z01vodvduei-:uvd 10 cm in front of the mirror on the mirror's axis. Where is the image locateded duuvi z:2odv0-8v1?

A. 20 cm behind the mirror

B. 20 cm in front of the mirror

C. 6.7 cm behind the mirror

D. 6.7 cm in front of the mirror

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77#

单选题 ( 1.0 分) 切至整卷模式搜藏此题

A concave spherical mirror has a focal length of 20 cm. An obj lkdjil. j:b7-ect is placed 30 cm in front of the mirror on the mirror's axis. Where is the image locatebl- jjl:7 i.dkd?

A. 12 cm behind the mirror

B. 12 cm in front of the mirror

C. 60 cm behind the mirror

D. 60 cm in front of the mirror

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78#

单选题 ( 1.0 分) 切至整卷模式搜藏此题

An object is 5.7 cm from a concave mirror. The image is 4.7 cm tall, and 10 cm0 6qm. -gpgwngh9n f;q from the mirror. How tall is the ob.nqf ngp-9g g60wh;q mject?

A. $12 \; cm$

B. $11 \; cm$

C. $8.2 \; cm$

D. $2.7 \; cm$

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79#

单选题 ( 1.0 分) 切至整卷模式搜藏此题

An object is placed 15 cm from a concave mirror of focal leng5 *o7 g gtn,c 5siwy3ti/xm*rgth 20 cm. The object is 4.0 cm tait3xogn5m wc,/g s*i 7yrtg5*ll. How tall is the image?

A. $1.0 \; cm$

B. $2.0 \; cm$

C. $8.0 \; cm$

D. $16 \; cm$

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80#

单选题 ( 1.0 分) 切至整卷模式搜藏此题

An object is 47.5 cm tall.kjta n+4y;g-61 jjac jm;at al*ft6p, The image is 38.6 cm tall, and 14.8 cm from the mirror. How far;*al tjyt6a f;1j,a-jkatc j 4g6+pnm is the object from the mirror?

A. $124 \; cm$

B. $47.6 \; cm$

C. $18.2 \; cm$

D. $12.0 \; cm$

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81#

单选题 ( 1.0 分) 切至整卷模式搜藏此题

A 1.4 cm tall object is 4.0 cm from a concave)n bvw,ues :gc6xx +l( mirror. If the image is 4.0 cm tall, how far is c:e,v n+(bxl)gxw u6sit from the mirror?

A. $11 \; cm$

B. $9.4 \; cm$

C. $1.4 \; cm$

D. $0.090 \; cm$

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82#

单选题 ( 1.0 分) 切至整卷模式搜藏此题

An object is placed 15 cm from a concave mirror of focal length 20 cm. The obje9j) ye ;n5zutf o;ui1pct is;;foeu9jp yz1ui 5tn) 4.0 cm tall. Where is the image located?

A. 12 cm behind the mirror

B. 12 cm in front of the mirror

C. 60 cm behind the mirror

D. 60 cm in front of the mirror

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83#

单选题 ( 1.0 分) 切至整卷模式搜藏此题

When a person stands 40 cm in front of a cosmetic mirror (cod.m f3wkpw i0)ncave mirror), the erect image is twice the size of the object. What is the focal length ok)f dmw30w.ipf the mirror?

A. $27 \; cm$

B. $40 \; cm$

C. $80 \; cm$

D. $160 \; cm$

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84#

单选题 ( 1.0 分) 切至整卷模式搜藏此题

A person's face is 30 cm in front of a concave,+y1jcqozi5j coj r46x 2:exe shaving mirror. If the image is an erect image 1.5 times as l xi21zjxoye6o: 4 ccqe,jj5r+arge as the object, what is the mirror's focal length?

A. $20 \; cm$

B. $50 \; cm$

C. $70 \; cm$

D. $90 \; cm$

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85#

单选题 ( 1.0 分) 切至整卷模式搜藏此题

An image is 4.0 cm behind a concavtuq6/oz ;2; ow zim/eje mirror with focal length 5.0 cm. Where is the o6u ;iw;/ze2 qotm /zjobject?

A. 2.2 cm in front of the mirror

B. 2.2 cm behind the mirror

C. 9.0 cm in front of the mirror

D. 1.0 cm behind the mirror

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86#

单选题 ( 1.0 分) 切至整卷模式搜藏此题

A convex spherical mirror / ponl2s;rk-8 g hro3ehas a focal length of -20 cm. An object is placed 10 ekr oplrs o2g3 /;h8-ncm in front of the mirror on the mirror's axis. Where is the image located?

A. 20 cm behind the mirror

B. 20 cm in front of the mirror

C. 6.7 cm behind the mirror

D. 6.7 cm in front of the mirror

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87#

单选题 ( 1.0 分) 切至整卷模式搜藏此题

A convex spherical mirm)sltt46u)ec14np*o v/n pdmror has a focal length of -20 cm. An object is placed 30 cm in front of the m)n)cm4 t6pvu*o te nspl4d1/mirror on the mirror's axis. Where is the image located?

A. 12 cm in front of the mirror

B. 60 cm behind the mirror

C. 60 cm in front of the mirror

D. none of the given answers

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88#

单选题 ( 1.0 分) 切至整卷模式搜藏此题

An object is 14 cm in front of a convex mirror. The image is 5.8 cm behvc6(j0vee qls( hc (f)ind the mirror. Wha6 0(e)vcs(e cfqlh(j vt is the focal length of the mirror?

A. -4.1 cm

B. -8.2 cm

C. -9.9 cm

D. -20 cm

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89#

单选题 ( 1.0 分) 切至整卷模式搜藏此题

An object is 8.90 cm tall. The image is 7.80 cm t9zkz1h a. xqk-all, and 14.8 cm from a convex mirror. What is the mirror's focalz kq.z19 xahk- length?

A. -120 cm

B. -105 cm

C. -16.9 cm

D. -13.0 cm

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90#

单选题 ( 1.0 分) 切至整卷模式搜藏此题

If a material has an index of refraction of 1.50, what is the speed of light- ( zb.pc(o odo)qnp 4txs4mr. through .md- x rbo4(s4)(pzo.c to qpnit?

A. $2.00 \times 10^{8} \; m/s$

B. $3.00 \times 10^{8} \; m/s$

C. $4.50 \times 10^{8} \; m/s$

D. $6.00 \times 10^{8} \; m/s$

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91#

单选题 ( 1.0 分) 切至整卷模式搜藏此题

A light ray in air is p h.iq/b0k )f68z,qn s h7owxpincident on an air to glass interface at an angle of $45^{\circ}$ and is refracted at an angle of $30^{\circ}$ to the normal. What is the index of refraction of the glass?

A. 1.23

B. 1.31

C. 1.41

D. 1.74

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92#

单选题 ( 1.0 分) 切至整卷模式搜藏此题

Light enters a substance from air a8xcgtmbb7* lw*c95igt an angle of $32.0^{\circ}$, and continues at an angle of $23.0^{\circ}$. What is the index of refraction of the substance?

A. 0.74

B. 1.11

C. 1.28

D. 1.36

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93#

单选题 ( 1.0 分) 切至整卷模式搜藏此题

Light passes from air to ve4hti.p(z0f fen6-lmw9s745 lg one water. The incoming ray is at an angle of $17.0^{\circ}$ to the normal. The index of refraction is 1.33. What is the angle in the water?

A. $22.9^{\circ}$

B. $22.6^{\circ}$

C. $18.3^{\circ}$

D. $12.7^{\circ}$

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94#

单选题 ( 1.0 分) 切至整卷模式搜藏此题

An oil layer that is 5.0 cm thick is spread smoothly and evenly ov0c mc,j pua 48gjws2g5er the surface of water on a windless day. What is the angle of refraction in the water for a ray of light that has an angle of inc5u sg2a0cg4wjjp8 c ,midence of $45^{\circ}$ as it enters the oil from the air above? (The index of refraction for oil is 1.15, and for water it is 1.33.)

A. $27^{\circ}$

B. $32^{\circ}$

C. $36^{\circ}$

D. $39^{\circ}$

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95#

单选题 ( 1.0 分) 切至整卷模式搜藏此题

A diver is 1.2 m beneath the surface of a still p f1vk( (rni/dfj6nq7vm.ojr ( ond of water. At what angle must the diver shine a beam of light toward the surface in ov7(n .6fq1r(j(mfvdkinr /j order for a person on a distant bank to see it? (The index of refraction for water is 1.33.)

A. $41^{\circ}$

B. $49^{\circ}$

C. $59^{\circ}$

D. $90^{\circ}$

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96#

单选题 ( 1.0 分) 切至整卷模式搜藏此题

A beam of light, traveling in air, strikes a plate of transparent materiaz2o6i +xzzt;tk/b tv 6c+p3ue 0yl ;qxl at an /0y 2vtzzu6olt +xzbet+ pk q3;6c xi;angle of incidence of $56.0^{\circ}$. It is observed that the reflected and refracted beams form an angle of $90.0^{\circ}$. What is the index of refraction of this material?

A. 1.40

B. 1.43

C. 1.44

D. 1.48

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97#

单选题 ( 1.0 分) 切至整卷模式搜藏此题

A beam of light traveling in air is incident on a slab of transparent m/j jfby9 )m3mpi3pxr0aterial. The 9mjmr0j 3/ pp iy3bx)fincident beam and the refracted beam make angles of $40^{\circ}$ and $26^{\circ}$ to the normal. What is the speed of light in the transparent material?

A. $1.0 \times 10^{8} \; m/s$

B. $2.0 \times 10^{8} \; m/s$

C. $2.3 \times 10^{8} \; m/s$

D. $3.0 \times 10^{8} \; m/s$

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98#

单选题 ( 1.0 分) 切至整卷模式搜藏此题

A substance has an i q*mdobc * m(25zfqwmx;ykw,djaf.*0ndex of refraction of 1.46. Light is passing through it at ,x(m0aj kzmqwbo*w. d2yfq5m ; *d*fc$53.0^{\circ}$. At what angle will it leave into the air?

A. It will not leave.

B. $59.1^{\circ}$

C. $43.2^{\circ}$

D. $33.2^{\circ}$

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99#

单选题 ( 1.0 分) 切至整卷模式搜藏此题

What is the critical angle for light travku uc uavba,,:qs2pyi8t5 )y(eling from crown glass (n = 1.52) into water (n8y)( iuu ya p5,a2: tvkscuqb, = 1.33)?

A. $42^{\circ}$

B. $48^{\circ}$

C. $57^{\circ}$

D. $61^{\circ}$

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100#

单选题 ( 1.0 分) 切至整卷模式搜藏此题

Lucite has an index of refraction of 1.50. What is ky)n l8f8lzbec6 xvkijy:,; jlpq (u0*f5cs-its critical angle of incidencee y5,x8cjfncl ; py*ufk q)zsi-6vll (j k:b08?

A. $11.6^{\circ}$

B. $15.4^{\circ}$

C. $41.8^{\circ}$

D. $87.4^{\circ}$

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101#

单选题 ( 1.0 分) 切至整卷模式搜藏此题

An optic fiber is made o wrwtl p+(0oy(dl):lcf clear plastic with index of refraction of 1.50. For what angle of incidence w0cl wll(:w prd (o)+tyill light remain within the plastic "guide"?

A. $>23.4^{\circ}$

B. $>38.3^{\circ}$

C. $>40.3^{\circ}$

D. $>41.8^{\circ}$

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102#

单选题 ( 1.0 分) 切至整卷模式搜藏此题

The critical angle for a substance/ 3ud3x0 zz tofs:hzjo8+; xp1w xy.qi is measured at $57.3^{\circ}$. Light enters from air at $45.0^{\circ}$. At what angle will it continue?

A. $34.7^{\circ}$

B. $45.0^{\circ}$

C. $53.7^{\circ}$

D. It will not continue, but be totally reflected.

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103#

单选题 ( 1.0 分) 切至整卷模式搜藏此题

Light enters a substance fr.cbi qe4zei45z brdpg 5)ch45 om air at $30.0^{\circ}$ to the normal. It continues through the substance at $23.0^{\circ}$ to the normal. What would be the critical angle for this substance?

A. $53.0^{\circ}$

B. $51.4^{\circ}$

C. $36.7^{\circ}$

D. $12.6^{\circ}$

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104#

单选题 ( 1.0 分) 切至整卷模式搜藏此题

An optical fiber is 1.0 meter long and hinzr 7;cao:df aw v o(;,rrt0h/k )gf6as a diameter of 20 mm. Its ends are perpendicular to its axis. Its index of refraction is 1.30. What is the maximum number of reflections a light ray entering one end will ma: ;fa70z t 6nfhk)iwrdr;( og orc,v/ake before it emerges from the other end?

A. 42,000

B. 26,000

C. 24,000

D. 18,000

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105#

单选题 ( 1.0 分) 切至整卷模式搜藏此题

An object is placed 40 cm in front of a 20 cm focal length converging .buc + odnbid05vj-(rq.wngr63.apelens. How far is the imad(ubc-vn + wgr3o.j0n5 pi6r.d qab.ege of this object from the lens?

A. $40 \; cm$

B. $20 \; cm$

C. $13 \; cm$

D. none of the given answers

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106#

单选题 ( 1.0 分) 切至整卷模式搜藏此题

An object is 12 cm in front of a converging l / bct 3eknhrdaa//(f1ens with focal length 4 cm. Where israane3t hcd/ bk1/( f/ the image?

A. 8.0 cm behind the lens

B. 6.0 cm in front of the lens

C. 6.0 cm behind the lens

D. 4.0 cm in front of the lens

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107#

单选题 ( 1.0 分) 切至整卷模式搜藏此题

An object is 15 mm in front i/alcsw8,c b/2ff0c. olp+klof a converging lens, and the image is 4.0 mm behind the lens. What is the focal length of thill a2,8fcb s/fop0 /ck+c w.le lens?

A. $11 \; mm$

B. $5.5 \; mm$

C. $3.8 \; mm$

D. $3.2 \; mm$

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108#

单选题 ( 1.0 分) 切至整卷模式搜藏此题

A 14-mm tall object is 4.0 mm from a converging lens. If the image is 4.0 )i3w;k i4 rhl)m-05fnjhzdjemm tall, how far ;kdmzln )j) ew-i0j3frhh 5i4is it from the lens?

A. $14 \; mm$

B. $8.7 \; mm$

C. $1.4 \; mm$

D. $1.1 \; mm$

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109#

单选题 ( 1.0 分) 切至整卷模式搜藏此题

When an object is 40 m in front of agwg2z)() v xjt converging lens the inverted image is half the size of the object. What is the focal length of this len(t2g)w)vj zxgs?

A. $13 \; cm$

B. $20 \; cm$

C. $40 \; cm$

D. $53 \; cm$

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110#

单选题 ( 1.0 分) 切至整卷模式搜藏此题

An image is 4.0 mm in front of a converging lens with focal length i,:jcnvo ;8mp *g(nf s/ lpm:w5.0 mm. Where is the o:lnj/m,ig:fmow8p*vc ;(s npbject?

A. 2.2 mm in front of the lens

B. 2.2 mm behind the lens

C. 9.0 mm behind the lens

D. 20 mm in front of the lens

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111#

单选题 ( 1.0 分) 切至整卷模式搜藏此题

An object is 4.1 cm tall, and 10.3 m qvoah+ds, +a4qb4s7cm from a converging lens. The image is virtual and 6.2 cm tall. What is the focal length of the lo4 qa+qhvs as+m d4,b7ens?

A. $6.8 \; cm$

B. $10 \; cm$

C. $16 \; cm$

D. $30 \; cm$

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112#

单选题 ( 1.0 分) 切至整卷模式搜藏此题

An object is 15.2 mm from a converghu/m;4p, spoxs)6 pa ping lens. The image is 4.0 mm tall, and 9.0 cm from the lens. How tallh);p sams64 poxp ,pu/ is the object?

A. $6.8 \; mm$

B. $5.4 \; mm$

C. $1.7 \; mm$

D. $0.68 \; mm$

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113#

单选题 ( 1.0 分) 切至整卷模式搜藏此题

When an object is placed 60 cm from a convpd24k) h) *pwyw09 wu uuav.e+udjg8 zerging lens, it forms a real image. When the object is moved to 40 cm from the lens, the image moves 10 cm far)+ du)u0 u4pkh y9d.gwwep zwvauj2*8ther from the lens. What is the focal length of the lens?

A. $20 \; cm$

B. $30 \; cm$

C. $40 \; cm$

D. $42 \; cm$

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114#

单选题 ( 1.0 分) 切至整卷模式搜藏此题

An object is placed at a distance of 30 cm from a thin convex lens. The lensdid,ptov 3u( (ex0kg9 has a focal length of 10 cm. What are the values, k,((g9 0v pxe3touddi respectively, of the image distance and lateral magnification?

A. 15 cm, 2.0

B. 25 cm, 1.0

C. 60 cm, -0.50

D. 15 cm, -0.50

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115#

单选题 ( 1.0 分) 切至整卷模式搜藏此题

An object is placed at 30nk dv nn,)k9q- cm in front of a diverging lens with a focal length of 10 cnd q-nk), kvn9m. What is the image distance?

A. $7.5 \; cm$

B. $-7.5 \; cm$

C. $15 \; cm$

D. $-15 \; cm$

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116#

单选题 ( 1.0 分) 切至整卷模式搜藏此题

An object is placed at 30 cm in front of a diverging lens with a(3g,tlt+nvy -mv9sep t ; *ojt1ctx+ w focal length of 10 cm. What is the ma*,y o vtes ; -l +gp+3t1n(tm9vwtxcjtgnification?

A. 0.25

B. -0.25

C. 0.67

D. -0.67

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117#

单选题 ( 1.0 分) 切至整卷模式搜藏此题

An object is 10.4 cm tall, andw*f 6:ypd/kj d 4.8 cm in front of a diverging lens. The image is dkjf6pwy d :/*4.0 cm from the lens. How tall is the image?

A. $13 \; cm$

B. $8.7 \; cm$

C. $5.4 \; cm$

D. $1.8 \; cm$

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118#

单选题 ( 1.0 分) 切至整卷模式搜藏此题

An object is 6.0 cm tall, and is in front of a n,-r+ aqznm+zo)c2xr diverging lens. The image is 2.5 cm tall, and 7.5 cm from the lens. What is the focal length of the l-2r,)++ zxzcan qornm ens?

A. -6.0 cm

B. -7.5 cm

C. -13 cm

D. -18 cm

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119#

单选题 ( 1.0 分) 切至整卷模式搜藏此题

An object is placed at a distance of 40 cm from a thin lens. f(xud v.4y3)m eup1zmy*yt5v If a virtual image forms at a dism 5x)(t1*u yyv 4mz.yp3vfde utance of 50 cm from the lens, on the same side as the object, what is the focal length of the lens?

A. $45 \; cm$

B. $75 \; cm$

C. $90 \; cm$

D. $200 \; cm$

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120#

单选题 ( 1.0 分) 切至整卷模式搜藏此题

How far from a lens of focal lengncn9rv o g/04yth 50 mm must the object be placed if it is to form a virtual image magnified in size by a factn4 oc0vrny/ g9or of three?

A. $33 \; mm$

B. $42 \; mm$

C. $48 \; mm$

D. $54 \; mm$

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121#

单选题 ( 1.0 分) 切至整卷模式搜藏此题

How far from a 50-mm focal length lens, such as is used in manyulf7 g5uf99xamb l: 56t1 unmi 35-mm cameras, must an object be positioned if it is to form a real image magnified in size by a factor of threiugul x9: 56nmauf1m bf7t l95e?

A. $46 \; mm$

B. $52 \; mm$

C. $58 \; mm$

D. $67 \; mm$

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122#

单选题 ( 1.0 分) 切至整卷模式搜藏此题

Two very thin lenses, each with focal length 20 cm, are placed in contact. Whayr / *mlxz kt73tpm.s(t is the focal length of (s m*pzr3k.xtty7m/l this compound lens?

A. $40 \; cm$

B. $20 \; cm$

C. $15 \; cm$

D. $10 \; cm$

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123#

单选题 ( 1.0 分) 切至整卷模式搜藏此题

A double convex (convex-convex) thin lens has radii of curvf2 qk0duv q :7em5,irxature 46 cm, and is made of glass of ind mk70i 2queq r5v:fd,xex of refraction n = 1.60. What is the focal length?

A. infinite

B. $38 \; cm$

C. $30 \; cm$

D. $18 \; cm$

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124#

单选题 ( 1.0 分) 切至整卷模式搜藏此题

A double convex lens made of glas/ywqt n,9y6oc1 g aena8dr-a *s (n = 1.50) has a radius of 40 cm on the front side and 30tao 1-/e86dcw,9y a gqa*nyrn cm on the back side. What is the focal length of the lens?

A. $11 \; cm$

B. $34 \; cm$

C. $80 \; cm$

D. $240 \; cm$

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125#

单选题 ( 1.0 分) 切至整卷模式搜藏此题

A biconvex lens is formed by us09: m85bccy-rrfhcby ing a piece of plastic (n = 1.70). The radius of the front surface is 20 cm and the radius of the back surface is 30 cm. What is the focal lengthr-9c hbmb 05ccyf yr8: of the lens?

A. $17 \; cm$

B. $86 \; cm$

C. $-86 \; cm$

D. $-17 \; cm$

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126#

单选题 ( 1.0 分) 切至整卷模式搜藏此题

A plano-convex lens is k3,8hfvr hm;bto have a focal length of 40 cm. It is made of glass of index of refractiohb kv3 m8h;rf,n
1.65. What radius of curvature is required?

A. $13 \; cm$

B. $26 \; cm$

C. $32 \; cm$

D. $36 \; cm$

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