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

1#

Reflection, refraction, and the formation of images by m)*ofh q gh9sgpik v(7-irrors and lenses has been succ-h9gs)vh igfp 7*o(kqessful 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 incidencelmr8 d 5ok62n+;hug6ca1t zuj

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 0r9botse (66cv sy4 phnfs 7szh b715usx s84emirrors work 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 image tdo(y 9q, s1u.)rl dnjrhat 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 images whic. e9b3m,: ug;6dy6lrlnyyzj wo+yp x(h

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 actu4a ho0ev4n0kially pass through the image location, and would not appear on paper or film placed at that location is referreda4e0o i4k vhn0 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 im4.llvdh,kn7 r6f9sfb c9ql 5rage location, and could appear on paper or film placed at the that locatif9 q4h ,ld9f.s5 6lrbvrnckl7 on 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 vi8l 8g3;ywnvi;k:o * wkukg nc,rtual image?

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 t pbcy yr0-1j5ce ti(1fhe outer surface of the se i(rbp1 f0yyt1-c5jcpherical shape 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 reflection takes place on the s-(7k peya25j iarvtu *7h kq5rpyc .7inner surface of the sphere r p7q5-7 ea*c hyyva2.ip5 k7skrju( tis 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 conmc xni*5oo(m9cave mirror is r, the 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 axis,:uv)-hr kza xz+nuf6 4 strikes the mirror's surface near its midpoint. After refv) z -a:ufx+zurkh46n lection, 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 on auxkrik+6wwbzc4 s8ipf il8 ise-*,l 2k00so9 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, traveling obliquely to a concave m1t 1z05r) nbch rxhqf2irror's axis, crosses the axis at the mirror'01ht1f )czb r2 5rnhxqs center of curvature before 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 throw x6pr/s /ql -lz6p0g;qxi w6u2 *hkmsugh the center of curvature is reflecwp2s x;xz/wqg0 r s-u/6ki p 6qlhm*6lted

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 oizopt*5l5 t; obliquely to a concave mirror's surface, crosses the axis at the mirror's focal point before striking the mirror's surface. Afl;tz5t op *oi5ter 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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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 v.(we y+ v2vxr5 gtsm+point is reflecteevwtv+ +(vs .gmr5y 2xd

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 ra1fraw( f+q1ps 1/t cdzys for finding the image position due to a curved mirrortrf sq fw(1pz11+/cd a.

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 its fu1yeu + lm9,6vbif7lm ocal 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's center of curvature. The image producyb.vpr6q- m+d ed by the mirror is locatdq mp-vr. y+b6ed

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 center of d ;z7r5( wiuiqgwhw n7z(/ qhcs(n5o2 curvature and its focal point. The image produced by the mirror is locate ;iznw hh(n ow(sur2c(qqzd7 7 55/iwgd

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 su2 0z5ku5depxwux3/ l krface and its focal point. The ima xk05xzp2/ ld35ek wuuge formed in 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 convexcap;9ksrwz 2(u76f nqh 8bl 2q mirror, at the same distance from it as its radius of curvat 9l2qs(q2k87;zwcbhaunp rf 6ure,

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 convex mirror, at the s qm+c34t9zpx yzybu(m /,fh5pame distance from it as its focal length,b 9xufyzm+cpyh 43mt(q, z 5/p

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 curved m qt vpia0u.qg;q. ojg0b,q 1-cirror you see a magnified image (a great big 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 sej-go0uc ;b.q,g q i10t aqpq.ve?

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 mirrors produce i( uqsdai9ikl-6d cd;*mages 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 mirbv8o2+n dh 5ferors 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 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 q0uxksev8yc .8y ;xl-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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29#

单选题 ( 1.0 分) 切至整卷模式搜藏此题

A single convex spherical mirror produces an image which bswv.s7b7 f- rj si4/nis

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 y*l v -z+)7psst9cj7oyo;trlfor a mirror 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 positie9e esa.9)spv..t qejve, 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 is negative, the image formed isj+ 1cc: ). ozw/sjmdkd

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 a n8y/ i pp,gn(m hxnce1lb0;9apositive 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, thjnc .2j*x0hyn).ur/nt:toc re image is

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 hfl.jd8b/xx v6(zdn m+y9*n hmagnification is larger than one, then the image is +ml.b/ v6 9x(yhnx8dzhnfj*d

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 w 6n qg4;s6absof the magnification is smaller than one, then the image is sq6 a4;swnbg6

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(q)dfrthev: ;jdo3-syj 0jo 4 of the 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 fastesw arlp/8g 9vs0t

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 of refraoeii x4dnr45yppoc , w5e+r.4ction

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 one for a medium would i4 j/mzulh/ 6)z lgoze-mply

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 ofp bt*et.iuk7 25ncs y, diamond is $2.42$. 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 incidence c3e 5znpu maeh27ri+6

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 aletj7n1t0 l r6 c:nfj e-,oy2jngle into a denser medium 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. Th -4qgp;v/m5f cl;wqfbe angle of refraction will be

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 air, is incident on a glass pmf,:y: sur k/.b9b )nir; nt :raikea0late 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 fiber optics is based bam wus.; (rv/o8bw8dg5)(i ln.u kkn 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 beam of light passing from w*as).u0eyf1 o z(ykuu*cym g 6ater 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 lensej- s9*+pnl3ntu+bcue s 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 atd1 3vhgyxhm.my-4hro+h f 8 .w-nw +qn 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 the center than the edges are calledmq:m zac:z y x0w6/3sh sk)1ob

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 atlu lr mah6tyshn6 z5p+/(t2g . the 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 are similar except that lens B is rated at 20 diopters, wht.( ;chyer07ms j6fr nereas lens A is rated at 10 diopters. The focal length of.tnfcm ry( s7h;j6e0r 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 the axis of a thin6vcp /)gyjflaj r21*e concave lens, strikes the lens near its midpoint. After trav*p/ jrlj1aegcvf y 6)2eling 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 parallel to the axis of a convex thin lens, s 8hno y;qpm7a)jl zwi /(q/p:ctrikes the lens near its midpoint. After traveling through theiz8/pcq wqnl a)/;7ypm: o(hj 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 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 fostw .9xs6 u)5qj-a6 nfqr )wtvr finding the image position due to a thin lensw-5 6 s a.us69nqq)f)rwtxtj v.

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 foxu6lyyy3 +p ,6k en:m(.uj9 rkftwuz 1cal length $f$. 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 focal leng7xvy2oa 6 u:*o3lla jith $f$. 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 focalarbe9n4o) z 5)lwp1ojsb g8f6 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 f c7eutf k:wd0aits537 ocal length $f$. 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 length 6sfk f(. ursi(w7;+-+ ks zdn)txpw rw$f$. 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 focal poin p ),g ok-e-takmeco*9 h78y4sos*frft. The image formed y-ko7p )meso *h9grf*cake-s8 ,f to4is

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 concav8l fca jv8h0c549srjgp()l mhe lenses

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 see through a magnifying gl gw75 d;3. 3sf7un1afrvquo+xgxsz0y ass 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 screen. Bhcv/)o -6nn, ns uxo0ufg9hq2etween the lamp and the screen is placed a converging lens of focal length 24 cm. The filament of the lamp can be imaged on the screen. As the lens position gh/nfx6-9h ,)o 2q s0nu ocvunis 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 lengthk8arco :c8ku0skvv- 5mmf 9 ;qs $f_1$ 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 cont54cfqn: t3xyzzv 9(mhact. If each has 3(z :9 qnc4tzyfhv xm5a focal length of 20 cm, how would you expect the combination 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 surfac,q0sjgk(aqx6 6nwr0tjs: k n: e with an angle of incidence of 0 w:6nxqnq(js r,s tk0k:6ja g$52^{\circ}$. 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 formed by tqx4; o;*peury o pud6l6,ct9 mb8blb3he mirrolqmdu; ,er*3tu6; b6bp8cxboy pl 9o 4r appears to be

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 yoovcf*z 0druuovcj/i* 28 r) /mu stand 0.75 m in front of a vertical planefcrur*u c2v*8ovzi)m 0 j//od mirror?

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 approachhunc+jyhk:3.se* : o m a vertical plane mirror at a speed of 2 mj*e ksounh3m:yc:h+ ./s?

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.7 b+xazfcn y0nf+c( 8p How far from the mirr0p+nbfy7nc+ (8 cazxf or is the focal point located?

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 x)ev4as3(vu l6n yz;jf 75agz a radius of 20 cm creates a real image 30 cm from the mirror. What is the object distance?z xye)7 jv f3gzl(asn 6u;45va

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 mirroj/0u .g;e2mo wm hdty;r, and the image is 3.0 cm in front of the mirror. What ijduo2mg; htm 0 eyw/;.s 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 mirror with focal length 3 cm.(dz kg e+/g;3zgnm o a(s+w7hi Where is the imageo7gd(wmg+he;nk gzz/( +as i 3?

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 obje 4q7g ;dee9wwuw au 3rao36(gact is placed 10 cm in front awow;ea4g7e3d gq 9u(u3w6 ra 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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77#

单选题 ( 1.0 分) 切至整卷模式搜藏此题

A concave spherical mirror has a focal len1 f5f,dke cok9gth of 20 cm. An object is placed 30 cm in front of the mirror on the mirror's axis. W 1kkfo5 9fcd,ehere 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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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. Theza94zryt6 v s7 image is 4.7 cm tall, and 10 cm from the mirror. How 6az9vr s4t7y ztall is the object?

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 xictf fc( g/ouly18(315 cm from a concave mirror of focal length 20 cm. The object is 4.0 cm tall. How tall is t x/8tcu(fli cg1foy(3he 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 ta6-(9gxrw0+xm4f le f,drfdiu 78 cepb ll. The image is 38.6 cm tall, and 14.8 cm from the mirror. How far isrir( ucf epwx 9dd+ gxf,06bm84-l7fe 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 fh3i jhf*b*pk* rom a concave mirror. If the image is 4.0 cm tall, how far is it fj3 b***i phhkfrom 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 fro 6bb z4s3h*rd sral9n mtbvu:03m8c8z m a concave mirror of focal length 20 cm. The object i *dvbmcrzl3sh8 3rb6 tza8s0: 4mnbu 9s 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 40e 4wcrij f1 x9f9bojxz4gl;3* cm in front of a cosmetic mirror (concave mirror), the erect image is twice ;fzjexxj4g bori39 94*wc1f lthe size of the object. What is the focal length of 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 shaving mirror. If the imp(inpbh6x2il/ hu8r: age is an e:lix8/h p(ri6hu2bpn rect image 1.5 times as large 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 concave mirror with focal length 5.0g)f cj,y*h0 xypc,n9 x:ehy6k cm. Where is the objeyh0, )xx6y ,n*eycc:pjkg9h fct?

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 has y:)kuz dq x52 zp,exl*a focal length of -20 cm. An object is placed 10 cm in front of the mirror on p*ku5qzxz d y:,l )2exthe 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 mirror has a focal length of -20 cm. A+**un7lzvzd t n object is placed 30 cm in front od+ltun z v*7z*f the 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 fron pnl4xvw41 wwgyku6of 4+8 0* k;(y0ltpjmevvt of a convex mirror. The image is 5.8 cm behind the mirror. What 0ny*vl4p;(k4 6vpo+l8u xwwf 4kj0 ygwev1t m 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 tall, and 14.8 cm frols v;d714 q woo8, dcqect4u6ym a convex mirror. What iol d e;4o1q t4y6 w8c7cuvds,qs the mirror's focal 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 lktbrjsq+ bz4hg6 39 :jight throujb4j+ks6r9b:z3 t qhg gh it?

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 incident on an air to glass interface rqs vjwj rgpkb 4g/ *knhqwy,l7:r4(c8-w1h-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 foh1yqex9.h,vk s xg8k ,1ix r1rom air at 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 water. The in+rqcj(i 1 zr ld;3iil0coming 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 over the suris.ge(-lqx;r face of water on a windless day. What is the angle of refraction in the water f-resl.; xg iq(or a ray of light that has an angle of incidence 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 pond of water. At what angle m6k-uwkz,;r1 igo* k uvk9wo(i: it0wnust the diver shine a beam of light toward the surface in order for a person on a distant bank to see it? (The index of r:iw6w,nu (k okkzi1g0;u *o - i9wvrtkefraction 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 ini71 xapab gvia)q 8s*05b:y5vgj ) tln air, strikes a plate of transparent material at an angle of incidence ofa0) pti5lx )j7nibga1 yb:qv8 s5vag* $56.0^{\circ}$. 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 az otkb1k/e.4u db6x xf-b.-pm slab of transparent material. The incident beam and the refrzpbtbx1 /6x.bou. -me dk f4-kacted 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 index of refraction of 1.46. Light is p ndza*gm1m2ok6p)u 0gassing through it at mzm dgu0og ) ap61nk2*$53.0^{\circ}$. 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 traveling from crown gl20z hdhve fhc*zd2 (6pass (n = 1.52) into water (n = fdvz6c2h2dhe (0*phz 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. Whit(f8on 3x;s.pe+ub 6u c3 h0hnya:oe at is its critical angle of incideoui .(f+euo:y3a;xpbc30hn8 eh6t nsnce?

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 of clear plastic with index of refraction of 1.50. For qwz(r5 2 , jd16w:n8/qnug u kl1mfve5hd rtw*what angle of incidence will light remain witt(mjlq fz1w eu8*nn 5vwdr,q5wu6 d2 rkh1:/ghin 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 is mu/ 67aay 5 +ipjtas(vi1qmj ;geasured 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 substanc 0f itwu7mfs 77o,id)ae from 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 has a diameter of 20 mm. Itja2wny;-jo/j ek6 12fqb sm z(s ends are perpendiculamkfqs 2j2-6e(jb w;/ jzna1oyr to its axis. Its index of refraction is 1.30. What is the maximum number of reflections a light ray entering one end will make 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 ll3o4favr6yfj hy 3* 7-lo;l s20 cm focal length converging lens. How far is the image of this object h 6l vjy3olfl7of3 la r*-y;s4from 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 lens with focalf,fr br0ndjy0: do(h 1 length 4 cm. Where is tf0d1 (ho0fr:bdr, y njhe 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 of a converging le qeelny1dws1bkr a- h9 :9ww9*ns, and the image is 4.0 mm behind the lens. What 1w r91k:wy*adbw enqe l 9hs9-is the focal length of the 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 in1shij (tovqd0+ 8cg .mage is 4.0 mm tall, how far is it from ttv(osi1q0d8+ h. ngjche 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 a converging lens the invertxpfte 5p(ln*64khn a+ed image is half the size of the object. What is the focal lenaelnnkh5t(*pp6x4f + gth of this lens?

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 5.0 mm. Whervyz4p( e(w h.(- szm.7iuka)i .cbqxve is tie -a)(ixzwb(hv scp(. mvy7 q..kuz 4he object?

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 10oc pe uyn.um,/s-r 4gdd8gol *p( .3lm.3 cm from a converging lens. The image is virtual and 6.2ddogen r-u lys3/8p(* . c,l4up.mog m cm tall. What is the focal length of the lens?

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 converging lens. The image is 4.0 mm talld))vp 5dj65gv8zofx m , and 9.0 cm frovo8 ) 5zdd6pmv5xf)j gm the lens. How tall 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 conver7 :qb- 3s5) z akhczlumxjv*y.ging lens, it forms a real image. When the ob3xc5 q:ua7h*vz)bmz sk l jy-.ject is moved to 40 cm from the lens, the image moves 10 cm farther 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 cmx hp8l/87nr 6 oam:giq from a thin convex lens. The lens has a focal length of 10 cm. What are the values, respa:h7x rg8pno/ 6m8 liqectively, 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 30 cm in front of a diverging lens wity h r5g;e22/;u 0:g2 kiykirvbfe.ivrh a focal length of 10 cm. Whaek2kbr2 gi yrh.;g;rie yu2f50 :iv/vt 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 z*cdbwcy ya-4, b+ -xly a--urin front of a diverging lens with a focal length of 10 cm. What is the magnif-y-+wlbd*4--,xy ay urz ba ccication?

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 talqcd7q y8y gtkk7y*h: :z+,x zbl, and 4.8 cm in front of a diverging lens. The image is 4.0 cm frdq7gcy,ybz 8th y zq+7kkx*: :om 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 diverging lens. The image is 2.r:t qv pn)aor89 v)fa*3yq9ge 5 cm tall, and 7.5 cm from the lens. What is the focal length))9 :8* rvvtqen93 agroyaqpf of the lens?

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 fr1m 0b/(jcqa 01dwn sdnom a thin lens. If a virtual image forms at a distance of 50 cm from the lens, on the same side as the obj0 b 0dnm1/jw(nqasd1c ect, 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 lbj:yb t)z6p6l 7hf xdn-,4 mspength 50 mm must the object be placed if it is to form a virtual image m)jd,b y:l -f6n p7mb6p hztx4sagnified in size by a factor 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 aswe1el 9 kssqlw9o) 0ihhqq+tx d2;5 *s is used in many 35-mm cameras, must an object be positioned if it is to form a real image magnifio9xhew 5t s0s)lkq9 ed;*s2hq i1wql+ed in size by a factor of three?

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 cmgjm4(c lgbd8h1ek;a3p)xnw : , are placed in contact. What is the foca; n(kpgw: ghj dm83 l4ebc)x1al length of 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-conve , fjxga7+ppc;x) thin lens has radii of curvature 46 cm, and is majpgca,7x ;p+fde of glass of index 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 glass (n = 1.50) has a radius of 40 cm 6rw:gwfa1g: s on the front side and 30 cm on the back side. What is the focal length of aws6: gg1f:wr 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 using a piece of plastic (n = 127g9ox0x *4k(gputi0:irzzh ye sr i; .70). The radius of the front surface is 20 cm and the hi0 x( rz9k2zi :74 oeg0r* gtxi;sypuradius of the back surface is 30 cm. What is the focal length 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 to have a fum*j ay,urz +,s-2 nkcocal length of 40 cm. It is made of glass of index of refractionj zumnksc -u,+2 a*yr,
1.65. What radius of curvature is required?

A. $13 \; cm$

B. $26 \; cm$

C. $32 \; cm$

D. $36 \; cm$

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81	82	83	84	85	86	87	88	89	90
91	92	93	94	95	96	97	98	99	100
101	102	103	104	105	106	107	108	109	110
111	112	113	114	115	116	117	118	119	120
121	122	123	124	125	126

1	2	3	4	5	6	7	8	9	10
11	12	13	14	15	16	17	18	19	20
21	22	23	24	25	26	27	28	29	30
31	32	33	34	35	36	37	38	39	40
41	42	43	44	45	46	47	48	49	50
51	52	53	54	55	56	57	58	59	60
61	62	63	64	65	66	67	68	69	70
71	72	73	74	75	76	77	78	79	80
81	82	83	84	85	86	87	88	89	90
91	92	93	94	95	96	97	98	99	100
101	102	103	104	105	106	107	108	109	110
111	112	113	114	115	116	117	118	119	120
121	122	123	124	125	126