Physics Unit23: Light and Geometric Optics

1#

Reflection, refraction, and the formation of images by mirrors 5;ia- + ss cdzkd+bxv/and lenses has been i+xa-kscd+ 5zvs/;db successful 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 incidencefrm-7xpm0u0 n

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 mirr7xh l5* noxy.kors 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 im27 q-)nwgotzklgnn 8 +age 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 in5z+v6c *qqvg 8bv +lhmages 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 imag -b3f7wk8cd,bt7wzjx) cii/ we location, and would not appt d wz7 7b/ wc-jf3cwxii,kb)8ear on paper 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 location, az ff s-+w-w5): rwaw(a k(hyb i(gs+bnnd could appear on paper or film placed at (wa hawf)b:(k-+ -5wgy+f swb zis(nrthe 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 vi ys1i:azl0i/j/cbt,h ( bnpo0 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 the outer surface o m iqsm4+f2ez7f the spherical shape is refemq2 zfe4m +is7rred 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 (zero fc5lv)- l1 jjq3the inner surface of the sphej rofq)zcv-l5 jl13(ere 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, tsdw.pqzxb+)/s t )fo 5he 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 m1/xvr 96umyx* (b hrnsjit30virror's axis, strikes the mirror's surface nearr96yb13i*n 0/tm vrhvjxx(su 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 on a path parallel to the axis is reflec5gtv06b :p +omwid thq,tg et7c).x8 ated

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 mirror'ss, 5ywl0*b t; wn,j;me*l9jh oev .vsm axis, crosses the axis at the mirror's center of curvature before striking the mirror's surface. After reflecjb9ly ew*t;jw5vhm,o*sel 0ms;, nv.tion, 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 t c9i c4pb*ob8t+9 m.e +qktbfkhrough the center of curvature is reflecit*qfe 9bc 8t o .b9bkck++pm4ted

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 tq hmz8-* aq /n1es 8ibd4tabj7o a concave mirror's surface, crosses the axis at the mirror's focal point before strhatbb8q/m-a 71z*n4 dsei8q jiking 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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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 rew/qwu:x5 dm/ px eq-c+r( ,smnflecterqe/q ,snp +5:(/ d-cwmwux mxd

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 pjg-/gg mu m-hnd3.su 0nt n15sosition due to a curved mirroru 5h/m-g nt.nssgugd31j-0n m.

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 focal point,1 yyfgvwq1+::bkah-et u g 6,fg2o-nt

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 jrc2-xodf48 u. The image produced by the cojdu2f4r- x8mirror 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'sy:g9e 8or.so guyu5k8pfdz )v/w lv5; center of curvature and its focal point. The image produced by the mirror is l8;5dlr kfsoz8 /)uyy5ew9 g.uvgp v:oocated

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 mirrorlh r ,:zk ovgh86hf8vpec /u0pr9h:w.'s surface and its focal point. The image formed in this calfw8o :ph 9grh uekp0ch/z.vh8vr :, 6se 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 conve w 6klnk)gvaw0bnd27f(m+n 5( (hbb 8h.wzurgx mirror, at the same distance from it as its radius of czfwbgban5 bkv nh(((wwur2d0h+gk.6 78l )nmurvature,

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 f 4:u 7ophj :qzd8a0nathe same distance from it as its focal lengto8znjha 40:au: 7pqdfh,

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 intc55f fyme 24aro a curved mirror 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 y fmcr42af55e 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 mirrors :q.x k2g z grazv s gpk c4h0ku-h-6+gsn8.2zgproduce 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 yb/k hlm35rp3which

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 p 3llzogz,r/ a2)p(1f/is bhgbroduces 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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29#

单选题 ( 1.0 分) 切至整卷模式搜藏此题

A single convex spherical mirror prchbf, v3,*pm *oj +fgmza5lt )oduces 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 mirror means:te vcx3(/cc.hv, w o/xupdh 0

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 positive, the xm2s hb g3,zqdv;a57v phd* j8image 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 formedapi (- + + :auuqoafwd3bti1f5zp.jwg5;g 9uf 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 magnification0i:k0 8bf-xkd2+jjid e g3u s )g6atmt is 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 ims wi0fdbox.okj3 +7c; y1dn* s

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 iswz;p4yi*3utln )ndx 4 larger than one, then the image is )x;t4w din l*np4uz3y

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 magnificgs,b y8ka4j*4r4 ok zcation is smaller than one, then the image isca4jzrg*o8kb,s4 k 4y

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 the magnification is e1+c 7l rzop3lea 6bwp0qual 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 fastesttf:cx w pdq,ci;(a,y,krar -oy b21q7

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 sudg-le3i r (ug3bstances, the index of 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 refractiu.c 41 0zsg)b9kcprsur+grp. on less than one 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 refractif . i)jgm(xe tf;e)q.von of 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 incidenc(2ncl w;mgj3)a *j( t+vjimloe

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 ang,imuww 832 npb9 -dy8*e ra.b xtkct4jle 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. The angle of refracti+pju3(d 3 9euzmq l8beon 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 zbo,b 4* ous-0xmhz,k 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 fiber optics is based wd ts th+ dk zug6+pn)91fs**ais

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 vbsv 5o1ussd)b;io9y 3hr(p5od3i k 9beam 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 lenses work iszt r6u:hp 6h9w

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 at the cocwex i)7bj+ +-l) cqdenter 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 th/i5gkt8v.m-hj,h vq 3j cbre*an 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 the3 p,- a)iylsiszr5jh2 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 r u:sr8q/,at+0yz.qf;pq goyc ated at 20 diopters, whereas lens A is rated at 10 diopters. The focal length of lens B isr8op.q, 0 yay;t szg/+uqq cf:

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 thin concavezh 4nkw8.dfp 8ds s7k1 lens, strikes the lens near its midpoint. After8nwh8kf 7sdp.ks4 1dz 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 para1yw :fd anxr**llel to the axis of a convex thin lens, strikes the lens near its midpoint. After traveling through the lens, this ray emerges traveling obli1 xn r:ydwa*f*quely 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 the image position due to ddnld2 l+ 0dm7hl 9n9da thin lens.dnhlm92 dd9d0dl+7 nl

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 sszi8gmcwz se;w) 3vy,3 gc .0length $f$. 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 len ,skagt9*g xmbw9ik,wv;0 wc 6gth $f$. 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 focal len nyp(aqw;fmz*liq8q :fa )+. qgth $f$. 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 fock( /mt:nv*3 wabb h*j,skp,shal 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-i11ewu +ooj9(jf6p5kkp xz aozl(s 6 length $f$. 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 point. The image fo xjg1us: trl)kd(1cm4rmed ():1tdslmu4rk xj c1gis

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 lens.qzkyq mlpowf3ibsh,)5 ,85p es

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 seak c( e01h9ega-asxw/ e 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 screen. Between the lam5u3 x8hf 2nhvjzz f+cc 6u4m(jp and the screen is placed a converging lens of focal length 24 cm. The fi52c8 m4uxjv fzfc z+h(n 6uhj3lament of the lamp 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 fy6mv7 ,iqsq*sjo 0/owjh u1s i )w() +wbt6ysxocal lengths $f_1$ 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 x5c/gcjlk ( 6fyjm+cr5u; g0yare placed in contact. If each has a focal length of 20 fy/0m clgc65kju(jry5;+cgx 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 surface with an angyp 7/fpn c4vw8dn(6gale of incidence of 6 nf8vcap7d (gwyp4 /n$52^{\circ}$. 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 mirror9suz(w)mfp 5 y. The image formed by the mirror appears tow()f9sy zu m5p 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 you stand 0.75 m in front ot ;vcy xq hk(k+gcyzr) x9 7b5x2:5ftpf a vertical plane mirror?9v(kx;5yt7 f2p+:ht xx gyrk5)qcbcz

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 n91n *gre e4yqimage when you approach a vertical plane mirror at a spe4*r 1eyng n9qeed of 2 m/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 curv4iz)e;l zeuk b48rn9 sb )wj+vature of 20 cm. How far from the mirror is the+ 49kw esez nlbu )jiz4r)v8;b 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 a radius of 20 cm creates a reah gb)7a( (suxrzma1g5/ cpr -ml image 30 cm from the mirror. What is the omr-uas b5cm)xg(71rzag / h p(bject 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 t gn--s9aa gi6 js,7uilhe image is 3.0 cm in front of the mirror. What is the focal lengthigln 7iasuja-g6s9- , 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 len 9grvn mwrf .rr;py*oq134tb: gth 3 cm. Where is the image?:3n1y94mv tfrwgr*;r.rqp bo

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 ovmz uczl(7 8ndt9dev, 9(au8 vbject is placed 10 cm in front of thvue dvv8aun 8zlm97t9c((z,d e 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 length of 20ctfig y8ivfiza- s0*-,i e)e8 cm. An object is placed 30 cm in es08vtfy) g*, ifi-ci zi-8ea front of the mirror on the mirror's axis. 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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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 tal.e cq h(n3iwwv6ns/b*d4q3sr l, and 10 cm from the mirror.3b3dsqhnsv4 qw*w6 ei/n c( r. How tall 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 15 cm from a concave mirror of focal length 20 cmz.7(t6io4+ audfy syb . The object is 4.0 cm tall. How tall is the imas.+4toa6u7 (yi dfbzyge?

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. Thexoh)7em.u/z x*t ja- e image is 38.6 cm tall, and 14.8 cm from the mirror. How far is the obje7/ zmoj.*-au t hx)eexct 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 mirror. If the image is 4.0 cm ydnmx u q5v:/rx34bg0tall, how farn q/urdx:4vg0b3y5mx is it 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. Tm8sz vb:h n*h5q/oorip- ;4 vohe object is 4.0 cm8z*n-v vopso/h ri hmq4o5:;b 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 jv4y*ac0 z 3 ak7lq*mwcosmetic mirror (concave mirror), the erect image is twice the size of tma *vq4ly 7j*w0ckz3ahe 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 )0wikx2mc t a3in front of a concave shaving mirror. If the image is an erect image 20ma 3ti xck)w1.5 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 j3*sbxmhzjd j/q ,jr3n19sp5mirror with focal length 5.0 cm. Where is the objecpxjd/ zjjb ,*q sr5s1n 39mjh3t?

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 a focal length of -20 cm. An object is placei;2 uccrmnsq2 s1:j/ giwdo1 7l7smo2d 10 cm in front of the mirror on the mirrl2wjm ;ns 1s rcu7qgd ioocs 7/mi22:1or'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. An object is9g u21gwww:)f;1pd wll f-l5vac4 fcb placed 30 cm in fron;1p:lcwu v -4l9)gfl5 wcad1 f2fbgwwt of 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 front of a convex mirrohmpt ;n7k(b:dxyh(u jnzke3*xuks 5 sx9(*6 dr. The image is 5.8 cm behind the mirror. What is thn td(mzupkh:5bxd h9ys7; 3( x(*6ne kkxsuj* e 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 talb4/*pf) rie yoo2nyr4l, and 14.8 cm from a convex mirror. What is the mirror's focal length?e4 i2b)y* /yr4 rofnpo

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 thebv 60l2*wwxpus6m o(e/wsg) a speed of light thro2*0wpw(sl v o u/ew )66bsxgamugh 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 ambm +9(zhe9ly ir 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 at anr2egzoor,/vn 9z u;w0 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 incoming rayi-+/nk lwvj :v 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+exn syla -6*)ref yt; cm thick is spread smoothly and evenly over the surface of water on a windlessax- +ee rnly* f)t;6ys day. What is the angle of refraction in the water for 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 surfacy a/ry5;/iyzfm(sx fv oj6h*y /n ;ol,e of a still pond of water. At what angle must 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 refraction for water is 1 fof5l;*smy xi/oyyz vhy,a6/;(nr j /.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 mi)6z2m pe -h1z:tr2t dvp pn5uaterial at an1n m2)pp5z: ttdrvpze-ihu62 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 o3u( lh,hjy-(zwb wj -on a slab of transparent material. The incident beam and the refracted beam (jh,3zo uw(yhj-w-lbmake 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 passing throughw ;hsi68er/ 3wj-kb nc it at w -cj e/kbh3ri8wn 6s;$53.0^{\circ}$. 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 lightpu* d8rl9a0 wk traveling from crown glass (n = 1.52) into water (np80 w k9l*daur = 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 its cri hvdis++j:c(w tical angle of incidence:c++ vswhj(d i?

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 plzm (yu. lgh26x9rzi q-astic with index of refraction of 1.50. For what angle of incidence will light remain wihri9-q (m6g2ly .uxzzthin 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 subut0(7nqpqrx /stance 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 from a*j0s7ntuyg 5jir 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 diameteslliqt+gc1a.,+ yab 4 r of 20 mm. Its ends are perpendicular to its axis. Itsb41y.s+g ltc,i la a+q 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 q4.9gtbz sy)jncu 05ba 20 cm focal length converging lens. How far is the image of this object .4t 9gyn5 q)b0cjzsubfrom 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 win8qo;zha)yrh; f7rd i*yk 5 i6zz/j9xth focal length 4 cm. Where is the imajh6*7ih;axro; zy5/ni)kd98qzfyz rge?

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 i mces95y5mn7 micu *j;,sfme9 n front of a converging lens, and the image is 4.0 mm behind the lens. What is the foc*mme feyi5um;5m99 cc7 ssj, nal 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 image i536omhexjy t 96c jvb)s 4.0 mm tall, how far is imt965covx6y h ejb3)jt 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 fronzjwu z7m:tc 71t of a converging lens the inverted image is half the size of the object. What is the focal length of this7u1c7jzmw :t z 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 o/icyl c 1aupq..1j8.iafv b*gp7i/rrf a converging lens with focal length 5.0 mm. Where is the objectruigbp7cvc.ia/ j .y. pi*8l1rqfa/1 ?

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 cm from a converging lens. n91sv7 whq: p/rb5suxd8 y3tw The image is virtual and 6.2 cm tall. What is thetn 3v/ p8sd:9b51wxswuy7q rh 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 mmb7qi0+ k( ahbq tall, and 9.0 cm from the le+ h0qqab7bk(ins. 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 / bb 6i 9icy9su/9cv hdsw4icwz,jmt/,0rz7s from a converging lens, it forms a real image. When the object is moved to 40 cm from the lens, the image moves 10 cm farther from the lens. What is0,i6rh 94/s wcwb ivsui z7cd9b mz9stjc,y// 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)7kl w-ofz)k)qa1 gw fau1du6 lens has a focal length of 10 cm. What are the values, respectively, of the image distance and 6uo)w w)g-zlqud)kfa117 akflateral 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 vu/ums2o2f 6kxfm1j v)4n9o07 hgv i rat 30 cm in front of a diverging lens with a focal length of 10 cm. What is vm /m)274i suv 1vkoxf2nj 06o ufhr9gthe 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 focal length .adk foka --4ymoi;x:of 10 cm. What is th ymxo:ao .fa ;di4k--ke magnification?

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, and 4.8 cm in front of a divergingr53ypxu-awho .1s4pf0 yai g 0bp6n8r0foi 3 w lens. The image is 4.0 cm from the lens. How tall 1 b 3opg-ryo4r5a8s.n0wa x0yu p0p36fwfi ih 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. Theu ;o0mup(pa -i image is 2.5 cm tall, and 7.5 cm from oum -;upiap0 (the lens. What is the focal length 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 from a thin lens. If a via,tr,xr x8 j+ gj8l,kqrtual image forms at a distance of 50 cm from thq,tr+8 kx ,lgrjj8xa,e 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 length 50 mm must the object be placed aij s8js4,2ss if it is to form a virtual image magnified in size by a fac ,4jjssas28is tor 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 len.:8jyy d) ezwhgth lens, such as is used in many 35-mm cameras, must an object be positioned if it is hyzw:)e j8 .ydto form a real image magnified 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 fm3k-d pkx1 en tgd6f5:/mt7jyocal length 20 cm, are placed in contact. What is the focal length -6/ ntgxmkdpyj 3tf1:kd7m 5e 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-convex) thin lens has radii of2.8qex- 5rjm9zwpdwi curvature 46 cm, and is mad 2dxw mpz 9-5eiwq.j8re 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 on the fraf8x.x1zyv790c ,kme muhvq0 49b gpuont side and 30 cm on the back side. What is the focal length 07vpb muhuzg1eqf0c 9 v x4.may9k,x8of 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 = 1.70). Thk+ s6nn8a ,rupe radius of the front surface is n,8 +rausn6kp 20 cm and the radius 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 focal )bblt,0 qm m-xe1udl7 h2n ye-length of 40 cm. It is made of glass of index on,)l tbxq-udyle1he m7b 0m- 2f refraction
1.65. What radius of curvature is required?

A. $13 \; cm$

B. $26 \; cm$

C. $32 \; cm$

D. $36 \; cm$

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