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

1#

Reflection, refraction, and the forma4qk*onyil pf ..0x ;eytion of images by mirrors and lenses has been successful d*xo.li4qy.e 0p f;knyescribed by the

A. wave model of light.

B. ray model of light.

C. particle model of light.

D. none of the given answers

绑定到本题的附件链接:
绑定到本题的上传图片:

参考答案:

进入本题讨论区，参与讨论

标记此题

2#

单选题 ( 1.0 分) 切至整卷模式搜藏此题

The angle of incidenrp*e2zd( d1ymce

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.

绑定到本题的附件链接:
绑定到本题的上传图片:

参考答案:

进入本题讨论区，参与讨论

标记此题

3#

单选题 ( 1.0 分) 切至整卷模式搜藏此题

The principle on which m)a zppw0pf .x8irrors work is

A. refraction.

B. polarization.

C. dispersion.

D. reflection.

绑定到本题的附件链接:
绑定到本题的上传图片:

参考答案:

进入本题讨论区，参与讨论

标记此题

4#

单选题 ( 1.0 分) 切至整卷模式搜藏此题

A plane mirror forms an image tqh 6vf.60 llr1;dgdb phat is

A. real and upright.

B. virtual and upright.

C. real and upside down.

D. virtual and upside down.

绑定到本题的附件链接:
绑定到本题的上传图片:

参考答案:

进入本题讨论区，参与讨论

本习题练习全部题目来源于51fly国际课程 (https://51fly.win)，学生可自助刷题练习，扫右侧二维码加微信，获取学习资料，答疑辅导
教师可以抽题组卷或一键复制他人试卷，布置为在线考试或在线作业，全自动判分成绩一键排序导出，省时省力

标记此题

5#

单选题 ( 1.0 分) 切至整卷模式搜藏此题

Plane mirrors produce image usi)ptd-2pk51xeg vti z(-z)s 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.

绑定到本题的附件链接:
绑定到本题的上传图片:

参考答案:

进入本题讨论区，参与讨论

标记此题

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 actua j;gv* xajt anmc(97*dlly pass through the image location, and would not appear on papat xj* *c7vgnma;dj9(er or film placed at that location is referred to as

绑定到本题的附件链接:
绑定到本题的上传图片:

参考答案:

进入本题讨论区，参与讨论

标记此题

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, andeim6g (mla 6r+ could appear on paper or l6+mmg(a6eri film placed at the that location is referred to as

绑定到本题的附件链接:
绑定到本题的上传图片:

参考答案:

进入本题讨论区，参与讨论

标记此题

8#

单选题 ( 1.0 分) 切至整卷模式搜藏此题

Is it possible to seep.xy1: te)r)cq:aavk1sy,i o a virtual 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.

绑定到本题的附件链接:
绑定到本题的上传图片:

参考答案:

进入本题讨论区，参与讨论

标记此题

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 surf/ho) i )lahp;bace of the spherical shape is referred to as a)p/)i; lhob ah

A. convex mirror.

B. concave mirror.

C. plane mirror.

D. double-sided mirror.

绑定到本题的附件链接:
绑定到本题的上传图片:

参考答案:

进入本题讨论区，参与讨论

标记此题

10#

单选题 ( 1.0 分) 切至整卷模式搜藏此题

A spherical mirror on which reflect36vps r /kxo;nzf9,mwb: hc/ rion takes place on the inner surface of the spherem3kvnx9br/cp,/6sh fz;o: w r is referred to as a

A. convex mirror.

B. concave mirror.

C. plane mirror.

D. double-sided mirror.

绑定到本题的附件链接:
绑定到本题的上传图片:

参考答案:

进入本题讨论区，参与讨论

标记此题

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 iyd8y 4d)krub+ s r, the focal length is

A. 2r

B. r

C. r/2

D. cannot be determined from the information given

绑定到本题的附件链接:
绑定到本题的上传图片:

参考答案:

进入本题讨论区，参与讨论

标记此题

12#

单选题 ( 1.0 分) 切至整卷模式搜藏此题

A light ray, traveli0 /hpp*vetn.by ,.tpjng parallel to a concave mirror's axis, strikes the mirror's surface near its midbjyv*n0htt .. pe/pp ,point. 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.

绑定到本题的附件链接:
绑定到本题的上传图片:

参考答案:

进入本题讨论区，参与讨论

本习题练习全部题目来源于51fly国际课程 (https://51fly.win)，学生可自助刷题练习，扫右侧二维码加微信，获取学习资料，答疑辅导
教师可以抽题组卷或一键复制他人试卷，布置为在线考试或在线作业，全自动判分成绩一键排序导出，省时省力

标记此题

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 t*jpy dgp ix,yg8/rsvs1 f2y54 he axis is reflected

A. back parallel to the axis.

B. back on itself.

C. through the focal point.

D. through the center of curvature.

绑定到本题的附件链接:
绑定到本题的上传图片:

参考答案:

进入本题讨论区，参与讨论

标记此题

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's a mh)rt mw/(7(rra5ajrarbs. 8 byy62sxis, crosses the axis at the mirror's center of curvature before striking the mirror's surface. After ( ar5rrw2m ba/.r)t rah8y m6by7( jssreflection, 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.

绑定到本题的附件链接:
绑定到本题的上传图片:

参考答案:

进入本题讨论区，参与讨论

标记此题

15#

单选题 ( 1.0 分) 切至整卷模式搜藏此题

Light arriving at a concave mj9p h4 (vx-hthf geqcu* n+o5-irror on a path through the center of curvature is reflechq hp4 5xocf(njg*ue-t9v-+ h ted

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.

绑定到本题的附件链接:
绑定到本题的上传图片:

参考答案:

进入本题讨论区，参与讨论

本习题练习全部题目来源于51fly国际课程 (https://51fly.win)，学生可自助刷题练习，扫右侧二维码加微信，获取学习资料，答疑辅导
教师可以抽题组卷或一键复制他人试卷，布置为在线考试或在线作业，全自动判分成绩一键排序导出，省时省力

标记此题

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 surface, cr.s.c wqoj4 jv8 :h3qlkosses the axis at the mirror's focal point before striking the mirror's surface. After reflection, 8j lh.voscj: q.kqw43 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.

绑定到本题的附件链接:
绑定到本题的上传图片:

参考答案:

进入本题讨论区，参与讨论

标记此题

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 t7 d m;hxnzwf a9a+/*ochrough the focal point is reflecteonhadawfz/ x7 9+mc*; d

A. back parallel to the axis.

B. back on itself.

C. through the focal point.

D. through the center of curvature.

绑定到本题的附件链接:
绑定到本题的上传图片:

参考答案:

进入本题讨论区，参与讨论

标记此题

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 positio,- cxrm tsr cmme .*px/4ym9l3n due to a curved mirrmecxc p/ 3mrt* xm.-mlsr4y,9or.

该题自我估分: (必填) (满分:1.0分)

绑定到本题的附件链接:
绑定到本题的上传图片: (问答题类型题目图片/附件必须插入上方文本框，否则会被移除题目绑定)

参考答案:

进入本题讨论区，参与讨论

标记此题

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,.7p(scoah2xu k lon,/aq* en- exactly at its 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.

绑定到本题的附件链接:
绑定到本题的上传图片:

参考答案:

进入本题讨论区，参与讨论

标记此题

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 dag (gt j+):o+h*c:ddnrmg/icenter of curvature. The image produced by tadhicg*)gdd tr:(nom:j +/ +ghe 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.

绑定到本题的附件链接:
绑定到本题的上传图片:

参考答案:

进入本题讨论区，参与讨论

标记此题

21#

单选题 ( 1.0 分) 切至整卷模式搜藏此题

An object is positioned betwee4x y);c+zbf2jwr b( lkn a concave mirror's center of curvature and its focal point. The image produced by the mirror is lofb+ ;4l2byk()rx cj zwcated

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.

绑定到本题的附件链接:
绑定到本题的上传图片:

参考答案:

进入本题讨论区，参与讨论

本习题练习全部题目来源于51fly国际课程 (https://51fly.win)，学生可自助刷题练习，扫右侧二维码加微信，获取学习资料，答疑辅导
教师可以抽题组卷或一键复制他人试卷，布置为在线考试或在线作业，全自动判分成绩一键排序导出，省时省力

标记此题

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 point. Ty)v.( smsn jw2he image fomnj vw ss.2y)(rmed in this case is

A. real and inverted.

B. real and erect.

C. virtual and erect.

D. virtual and inverted.

绑定到本题的附件链接:
绑定到本题的上传图片:

参考答案:

进入本题讨论区，参与讨论

标记此题

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 fromrcg9 ;dj+to( k9 )/bzy/,z mrnbi:r-cc ui4 xa it as its radius of curvature,/4gua-,km) t 9x z9c (rrzr ;d+j/oiybc: ncbi

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.

绑定到本题的附件链接:
绑定到本题的上传图片:

参考答案:

进入本题讨论区，参与讨论

本习题练习全部题目来源于51fly国际课程 (https://51fly.win)，学生可自助刷题练习，扫右侧二维码加微信，获取学习资料，答疑辅导
教师可以抽题组卷或一键复制他人试卷，布置为在线考试或在线作业，全自动判分成绩一键排序导出，省时省力

标记此题

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 7(wwsr-.sm gebdlb0ns.g ti, p *q)k5 same distance from it as its focnw 0 lb,gqigdw7..mts5k ep-(s*srb )al length,

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.

绑定到本题的附件链接:
绑定到本题的上传图片:

参考答案:

进入本题讨论区，参与讨论

本习题练习全部题目来源于51fly国际课程 (https://51fly.win)，学生可自助刷题练习，扫右侧二维码加微信，获取学习资料，答疑辅导
教师可以抽题组卷或一键复制他人试卷，布置为在线考试或在线作业，全自动判分成绩一键排序导出，省时省力

标记此题

25#

单选题 ( 1.0 分) 切至整卷模式搜藏此题

Sometimes when you look into a curved mirror you see a muosb* 2jy8ogfxf5,jv+ i;l lh( q ,lu4agnified 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 q( x+bjoflg2,;uujfsl,8liy 5o v h4*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.

绑定到本题的附件链接:
绑定到本题的上传图片:

参考答案:

进入本题讨论区，参与讨论

标记此题

26#

单选题 ( 1.0 分) 切至整卷模式搜藏此题

Concave spherical mirroe+g3il ztn, -ors 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.

绑定到本题的附件链接:
绑定到本题的上传图片:

参考答案:

进入本题讨论区，参与讨论

标记此题

27#

单选题 ( 1.0 分) 切至整卷模式搜藏此题

Convex spherical mirrors produc8 :r2puj gdxb 7tp7jf:e 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.

绑定到本题的附件链接:
绑定到本题的上传图片:

参考答案:

进入本题讨论区，参与讨论

标记此题

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 0pwmkhj n8q 2g e31lq1 )0 ep4xv9aczewhich 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 $f$.

绑定到本题的附件链接:
绑定到本题的上传图片:

参考答案:

进入本题讨论区，参与讨论

标记此题

29#

单选题 ( 1.0 分) 切至整卷模式搜藏此题

A single convex spherical mirror produces an irb; (eoe, bmu:sbsa3+ mage 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 $f$.

绑定到本题的附件链接:
绑定到本题的上传图片:

参考答案:

进入本题讨论区，参与讨论

本习题练习全部题目来源于51fly国际课程 (https://51fly.win)，学生可自助刷题练习，扫右侧二维码加微信，获取学习资料，答疑辅导
教师可以抽题组卷或一键复制他人试卷，布置为在线考试或在线作业，全自动判分成绩一键排序导出，省时省力

标记此题

30#

单选题 ( 1.0 分) 切至整卷模式搜藏此题

A negative magnification for a mirg skqqoj+ j4b vr;qjp/3b(2o+m :f6 amror 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.

绑定到本题的附件链接:
绑定到本题的上传图片:

参考答案:

进入本题讨论区，参与讨论

标记此题

31#

单选题 ( 1.0 分) 切至整卷模式搜藏此题

If the image distance is pommhlk z5. a /3r5es.zi0rpe*g sitive, the image formed is

A. a real image.

B. a virtual image.

C. either a real or virtual image.

D. can not be determined.

绑定到本题的附件链接:
绑定到本题的上传图片:

参考答案:

进入本题讨论区，参与讨论

标记此题

32#

单选题 ( 1.0 分) 切至整卷模式搜藏此题

If the image distance rl5(p 8b*g 7*uxxuwxnj0ata:is negative, the image formed is

A. real image.

B. virtual image.

C. either a real or virtual image.

D. can not be determined.

绑定到本题的附件链接:
绑定到本题的上传图片:

参考答案:

进入本题讨论区，参与讨论

本习题练习全部题目来源于51fly国际课程 (https://51fly.win)，学生可自助刷题练习，扫右侧二维码加微信，获取学习资料，答疑辅导
教师可以抽题组卷或一键复制他人试卷，布置为在线考试或在线作业，全自动判分成绩一键排序导出，省时省力

标记此题

33#

单选题 ( 1.0 分) 切至整卷模式搜藏此题

If the magnification i86f73;bh+jbhsd q hy ak2v d+ksxcv92s a positive value, the image is

A. upright.

B. inverted.

C. enlarged.

D. shrunk.

绑定到本题的附件链接:
绑定到本题的上传图片:

参考答案:

进入本题讨论区，参与讨论

标记此题

34#

单选题 ( 1.0 分) 切至整卷模式搜藏此题

If the magnification is a negative v fqoxhf,qib2 39.g:svalue, the image is

A. upright.

B. inverted.

C. enlarged.

D. shrunk.

绑定到本题的附件链接:
绑定到本题的上传图片:

参考答案:

进入本题讨论区，参与讨论

本习题练习全部题目来源于51fly国际课程 (https://51fly.win)，学生可自助刷题练习，扫右侧二维码加微信，获取学习资料，答疑辅导
教师可以抽题组卷或一键复制他人试卷，布置为在线考试或在线作业，全自动判分成绩一键排序导出，省时省力

标记此题

35#

单选题 ( 1.0 分) 切至整卷模式搜藏此题

If the absolute value of the magnification ishe 5wiqs871 tn larger than one, then the image is s5qewh1 it87n

A. larger than the object.

B. the same size as the object.

C. smaller than the object.

D. can not be determined.

绑定到本题的附件链接:
绑定到本题的上传图片:

参考答案:

进入本题讨论区，参与讨论

本习题练习全部题目来源于51fly国际课程 (https://51fly.win)，学生可自助刷题练习，扫右侧二维码加微信，获取学习资料，答疑辅导
教师可以抽题组卷或一键复制他人试卷，布置为在线考试或在线作业，全自动判分成绩一键排序导出，省时省力

标记此题

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 smaller than one, then thef1itu6q9th./ i h:0:arr xawp image i ::x9p1rhfi6aq0.itua h/wt rs

A. larger than the object.

B. the same size as the object.

C. smaller than the object.

D. can not be determined.

绑定到本题的附件链接:
绑定到本题的上传图片:

参考答案:

进入本题讨论区，参与讨论

标记此题

37#

单选题 ( 1.0 分) 切至整卷模式搜藏此题

If the absolute value of the magnn/s( yw sb)qo3 s+yg3zification 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.

绑定到本题的附件链接:
绑定到本题的上传图片:

参考答案:

进入本题讨论区，参与讨论

标记此题

38#

单选题 ( 1.0 分) 切至整卷模式搜藏此题

Light travels fastest) re2xpuin dml3d 183e

A. in a vacuum.

B. through water.

C. through glass.

D. through diamond.

绑定到本题的附件链接:
绑定到本题的上传图片:

参考答案:

进入本题讨论区，参与讨论

标记此题

39#

单选题 ( 1.0 分) 切至整卷模式搜藏此题

For all transparent material substances, the 8lf;ipe9p l :w.cj if;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.

绑定到本题的附件链接:
绑定到本题的上传图片:

参考答案:

进入本题讨论区，参与讨论

标记此题

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 me/gm h./wbk btvvjz6a56 tm;:kdium 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.

绑定到本题的附件链接:
绑定到本题的上传图片:

参考答案:

进入本题讨论区，参与讨论

本习题练习全部题目来源于51fly国际课程 (https://51fly.win)，学生可自助刷题练习，扫右侧二维码加微信，获取学习资料，答疑辅导
教师可以抽题组卷或一键复制他人试卷，布置为在线考试或在线作业，全自动判分成绩一键排序导出，省时省力

标记此题

41#

单选题 ( 1.0 分) 切至整卷模式搜藏此题

The index of refraction of4spk4.onr r v6h*2hqz,s y7uf 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.

绑定到本题的附件链接:
绑定到本题的上传图片:

参考答案:

进入本题讨论区，参与讨论

标记此题

42#

单选题 ( 1.0 分) 切至整卷模式搜藏此题

The angle of incidens- ,3tot c0oxuh6l)jo ce

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.

绑定到本题的附件链接:
绑定到本题的上传图片:

参考答案:

进入本题讨论区，参与讨论

标记此题

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 medium i2ee,-uap f6skrh b 8b1s refracted

A. toward the normal.

B. away from the normal.

C. parallel to the normal.

D. equally.

绑定到本题的附件链接:
绑定到本题的上传图片:

参考答案:

进入本题讨论区，参与讨论

标记此题

44#

单选题 ( 1.0 分) 切至整卷模式搜藏此题

Light enters air from water. pwran+z 6i (n l6i gnlm54c8:mThe 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.

绑定到本题的附件链接:
绑定到本题的上传图片:

参考答案:

进入本题讨论区，参与讨论

本习题练习全部题目来源于51fly国际课程 (https://51fly.win)，学生可自助刷题练习，扫右侧二维码加微信，获取学习资料，答疑辅导
教师可以抽题组卷或一键复制他人试卷，布置为在线考试或在线作业，全自动判分成绩一键排序导出，省时省力

标记此题

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 glasx9qk p3 tt5k2bs 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.

绑定到本题的附件链接:
绑定到本题的上传图片:

参考答案:

进入本题讨论区，参与讨论

标记此题

46#

单选题 ( 1.0 分) 切至整卷模式搜藏此题

The principle on which fiber optics is bol7ry2az c96 9aodjc ;ased is

A. refraction.

B. polarization.

C. dispersion.

D. total internal reflection.

绑定到本题的附件链接:
绑定到本题的上传图片:

参考答案:

进入本题讨论区，参与讨论

本习题练习全部题目来源于51fly国际课程 (https://51fly.win)，学生可自助刷题练习，扫右侧二维码加微信，获取学习资料，答疑辅导
教师可以抽题组卷或一键复制他人试卷，布置为在线考试或在线作业，全自动判分成绩一键排序导出，省时省力

标记此题

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 water ir htc7jc:ebcy )ir3ta4:( ,canto 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.

绑定到本题的附件链接:
绑定到本题的上传图片:

参考答案:

进入本题讨论区，参与讨论

标记此题

48#

单选题 ( 1.0 分) 切至整卷模式搜藏此题

The principle on which l1i-l4dusu 5cdenses work is

A. refraction.

B. polarization.

C. dispersion.

D. total internal reflection.

绑定到本题的附件链接:
绑定到本题的上传图片:

参考答案:

进入本题讨论区，参与讨论

本习题练习全部题目来源于51fly国际课程 (https://51fly.win)，学生可自助刷题练习，扫右侧二维码加微信，获取学习资料，答疑辅导
教师可以抽题组卷或一键复制他人试卷，布置为在线考试或在线作业，全自动判分成绩一键排序导出，省时省力

标记此题

49#

单选题 ( 1.0 分) 切至整卷模式搜藏此题

Lenses that are thickest ata r g(5hn,tgd, the center called

A. converging lenses.

B. diverging lenses.

C. either converging or diverging lens.

D. can not be determined.

绑定到本题的附件链接:
绑定到本题的上传图片:

参考答案:

进入本题讨论区，参与讨论

本习题练习全部题目来源于51fly国际课程 (https://51fly.win)，学生可自助刷题练习，扫右侧二维码加微信，获取学习资料，答疑辅导
教师可以抽题组卷或一键复制他人试卷，布置为在线考试或在线作业，全自动判分成绩一键排序导出，省时省力

标记此题

50#

单选题 ( 1.0 分) 切至整卷模式搜藏此题

Lenses that are thinner at ilu ; dujrkrcluw1 -)2x*)w ;nthe center than the edges are called

A. converging lenses.

B. diverging lenses.

C. either converging or diverging lens.

D. can not be determined.

绑定到本题的附件链接:
绑定到本题的上传图片:

参考答案:

进入本题讨论区，参与讨论

标记此题

51#

单选题 ( 1.0 分) 切至整卷模式搜藏此题

Lenses that are thicker w veu*f+.6exy+ict7nk/s m0kat 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.

绑定到本题的附件链接:
绑定到本题的上传图片:

参考答案:

进入本题讨论区，参与讨论

标记此题

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 7v**x7m8rm ubcst9 fo is rated at 20 diopters, whereas lens A is rac89f7 v7uts mrobx**mted 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.

绑定到本题的附件链接:
绑定到本题的上传图片:

参考答案:

进入本题讨论区，参与讨论

标记此题

53#

单选题 ( 1.0 分) 切至整卷模式搜藏此题

A light ray, traveling parallel to t: 3c zr3 ffdxe1v9oj(-8cz v tqi,c6imhe axis of a thin concave lens, strikes the lens near its midpoint. After traveling though 9c c3,vf6fj8 i:mzzq(3 tei cd-x1vorthe 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.

绑定到本题的附件链接:
绑定到本题的上传图片:

参考答案:

进入本题讨论区，参与讨论

标记此题

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, strikes theh7zu3 /oolr- l-s/gbv lens near its midpoint. After travelillo -/zoushvr-7b/g3 ng through 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 its focal point.

绑定到本题的附件链接:
绑定到本题的上传图片:

参考答案:

进入本题讨论区，参与讨论

标记此题

55#

问答题 ( 1.0 分) 切至整卷模式搜藏此题

State how to draw the three rays forfm2 wkwkv8g8dedi 70)*+t fmm finding the image position due to a thin lenw k7mi*k+ 2vd8dw) emgftm8f0 s.

该题自我估分: (必填) (满分:1.0分)

绑定到本题的附件链接:
绑定到本题的上传图片: (问答题类型题目图片/附件必须插入上方文本框，否则会被移除题目绑定)

参考答案:

进入本题讨论区，参与讨论

本习题练习全部题目来源于51fly国际课程 (https://51fly.win)，学生可自助刷题练习，扫右侧二维码加微信，获取学习资料，答疑辅导
教师可以抽题组卷或一键复制他人试卷，布置为在线考试或在线作业，全自动判分成绩一键排序导出，省时省力

标记此题

56#

单选题 ( 1.0 分) 切至整卷模式搜藏此题

A convex lens has focal lejj)vmeaoy0,,alxyq6(h mq* *ngth $f$. 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 $f$.

绑定到本题的附件链接:
绑定到本题的上传图片:

参考答案:

进入本题讨论区，参与讨论

标记此题

57#

单选题 ( 1.0 分) 切至整卷模式搜藏此题

A convex lens has a focal lmjb: k ;my2 6 shyr6b41bjem+jength $f$. 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 $2f$.

绑定到本题的附件链接:
绑定到本题的上传图片:

参考答案:

进入本题讨论区，参与讨论

标记此题

58#

单选题 ( 1.0 分) 切至整卷模式搜藏此题

A convex lens has a fof8+b bat 3jh w:dqd04kcal 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 $f$.

绑定到本题的附件链接:
绑定到本题的上传图片:

参考答案:

进入本题讨论区，参与讨论

标记此题

59#

单选题 ( 1.0 分) 切至整卷模式搜藏此题

A convex lens has a focal lengthr; q,btzatd *:xt;m;g 4vl9xg $f$. 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.

绑定到本题的附件链接:
绑定到本题的上传图片:

参考答案:

进入本题讨论区，参与讨论

标记此题

60#

单选题 ( 1.0 分) 切至整卷模式搜藏此题

A convex lens has a focal lengta64yh7 zju; :8s uzr 5e2xxab2g iye/mh $f$. 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 $f$.

绑定到本题的附件链接:
绑定到本题的上传图片:

参考答案:

进入本题讨论区，参与讨论

标记此题

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*y uc pxyu(5d0debc77s4 wa2hks)f9f rmed ihwbks)acy047 52pu*(u9 yff de7s dcxs

A. virtual and erect.

B. virtual and inverted.

C. real and erect.

D. real and inverted.

绑定到本题的附件链接:
绑定到本题的上传图片:

参考答案:

进入本题讨论区，参与讨论

标记此题

62#

单选题 ( 1.0 分) 切至整卷模式搜藏此题

The images formed by )r6mp86bx y:+*ehys2xg hq)odgyq8 gconcave 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.

绑定到本题的附件链接:
绑定到本题的上传图片:

参考答案:

进入本题讨论区，参与讨论

标记此题

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 glass isqolfiz3 .,t vgo/ ke9;

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.

绑定到本题的附件链接:
绑定到本题的上传图片:

参考答案:

进入本题讨论区，参与讨论

标记此题

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. Bezll.qew u+).v0l jb 2ytween 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 l+.yu l.zjl)evwb0q 2 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.

绑定到本题的附件链接:
绑定到本题的上传图片:

参考答案:

进入本题讨论区，参与讨论

标记此题

65#

单选题 ( 1.0 分) 切至整卷模式搜藏此题

Two thin lenses, of focal o;-;+uohfoqz qyvi61dp 4nw)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. $f_1 f_2/(f_1 + f_2)$.

绑定到本题的附件链接:
绑定到本题的上传图片:

参考答案:

进入本题讨论区，参与讨论

本习题练习全部题目来源于51fly国际课程 (https://51fly.win)，学生可自助刷题练习，扫右侧二维码加微信，获取学习资料，答疑辅导
教师可以抽题组卷或一键复制他人试卷，布置为在线考试或在线作业，全自动判分成绩一键排序导出，省时省力

标记此题

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 ec- de.xl1qao7cfkg1 6 ach has a focal length of 20 cm, how would you expect thef .ac 7e1o k16-lgxdqc 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

绑定到本题的附件链接:
绑定到本题的上传图片:

参考答案:

进入本题讨论区，参与讨论

标记此题

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.

绑定到本题的附件链接:
绑定到本题的上传图片:

参考答案:

进入本题讨论区，参与讨论

标记此题

68#

单选题 ( 1.0 分) 切至整卷模式搜藏此题

A laser beam strikes a plan)ab/ o8gb -injkle 94he's reflecting surface with an angle of incidence of -h4g n/9elj8 okb)iab$52^{\circ}$. What is the angle between the incident ray and the reflected ray?

A. $52^{\circ}$

B. $105^{\circ}$

C. $45^{\circ}$

D. $90^{\circ}$

绑定到本题的附件链接:
绑定到本题的上传图片:

参考答案:

进入本题讨论区，参与讨论

标记此题

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 ie;oihd/u 5wf2mage formed by the mirror ap h2d/fuw e;5iopears 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.

绑定到本题的附件链接:
绑定到本题的上传图片:

参考答案:

进入本题讨论区，参与讨论

标记此题

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 fron 5fkqa-jfji ;,ukq9uzls-wy /g.e 81qqq+np 7 t of a vertical plane mirrqjjsfgqpq8 ;9ae-, fl7.1ynizw5ku /-k+qqu or?

A. $0.75 \; m$

B. $1.5 \; m$

C. $3.0 \; m$

D. none of the given answers

绑定到本题的附件链接:
绑定到本题的上传图片:

参考答案:

进入本题讨论区，参与讨论

标记此题

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 vert;3,q p5)fhte4nf dxcu ical plane mirror atu4fhn) c5; ed3qtpx f, a speed of 2 m/s?

A. 1 m/s

B. 2 m/s

C. 4 m/s

D. none of the given answers

绑定到本题的附件链接:
绑定到本题的上传图片:

参考答案:

进入本题讨论区，参与讨论

标记此题

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 cuo(/nybw eas ,0)n;de drvature of 20 cm. How far from the mirror is the focal point / 0edweb),s( adno;ynlocated?

A. $10 \; cm$

B. $20 \; cm$

C. $30 \; cm$

D. $40 \; cm$

绑定到本题的附件链接:
绑定到本题的上传图片:

参考答案:

进入本题讨论区，参与讨论

标记此题

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 c/1hdlv5,s 3xn 1era2ta mpuq3reates a real image 30 cm from the mirror. What is the object distan/rq d35vam,ht1a1lnus x 3ep2ce?

A. $20 \; cm$

B. $15 \; cm$

C. $7.5 \; cm$

D. $5.0 \; cm$

绑定到本题的附件链接:
绑定到本题的上传图片:

参考答案:

进入本题讨论区，参与讨论

本习题练习全部题目来源于51fly国际课程 (https://51fly.win)，学生可自助刷题练习，扫右侧二维码加微信，获取学习资料，答疑辅导
教师可以抽题组卷或一键复制他人试卷，布置为在线考试或在线作业，全自动判分成绩一键排序导出，省时省力

标记此题

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 i*0l)x/mkj+6 or de4qwq ylr,kmage is 3.0 cm in front of / yl)emkr wxor60 q ,4+kq*ldjthe mirror. What is the focal length of the mirror?

A. $15 \; cm$

B. $4.0 \; cm$

C. $2.4 \; cm$

D. $1.3 \; cm$

绑定到本题的附件链接:
绑定到本题的上传图片:

参考答案:

进入本题讨论区，参与讨论

标记此题

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 miq71f)xuww() w)cqlk , btgi(y rror with focal length 3 cm. Where is the image)k,b(cw )y1tqx filw wuq(g 7)?

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

绑定到本题的附件链接:
绑定到本题的上传图片:

参考答案:

进入本题讨论区，参与讨论

本习题练习全部题目来源于51fly国际课程 (https://51fly.win)，学生可自助刷题练习，扫右侧二维码加微信，获取学习资料，答疑辅导
教师可以抽题组卷或一键复制他人试卷，布置为在线考试或在线作业，全自动判分成绩一键排序导出，省时省力

标记此题

76#

单选题 ( 1.0 分) 切至整卷模式搜藏此题

A concave spherical m9:/ ch6wh h 8w;ooelogirror has a focal length of 20 cm. An object is placed 10 cm in front of the mirror on the hwo e l6ho8wgcoh:;9/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

绑定到本题的附件链接:
绑定到本题的上传图片:

参考答案:

进入本题讨论区，参与讨论

标记此题

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 object is a ma knj yc+,)4ub/ zdq+v:+vcplaced 30 cm in front of the mirror on the mirror's axis. Where is the im):4bv+zy+kca +/unqv c admj,age 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

绑定到本题的附件链接:
绑定到本题的上传图片:

参考答案:

进入本题讨论区，参与讨论

标记此题

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, and7mx-09n i8;yo5aniih ;ojpnsrpa 6 2d 10 cm from the mirror. How tall is thesj;a;no2-io pp0r985nyahxmnid 6 7 i object?

A. $12 \; cm$

B. $11 \; cm$

C. $8.2 \; cm$

D. $2.7 \; cm$

绑定到本题的附件链接:
绑定到本题的上传图片:

参考答案:

进入本题讨论区，参与讨论

标记此题

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 cm. Thei;st(mdjrlt0t smt44(y*0 *5 dyln bp object is 4.0 cm tall. How tall s54 stpbmiy dtm0yn 4r;t0 t*(*j(ldl is the image?

A. $1.0 \; cm$

B. $2.0 \; cm$

C. $8.0 \; cm$

D. $16 \; cm$

绑定到本题的附件链接:
绑定到本题的上传图片:

参考答案:

进入本题讨论区，参与讨论

标记此题

80#

单选题 ( 1.0 分) 切至整卷模式搜藏此题

An object is 47.5 cm tall. w 9:yq; fgejd 1)nq0o5kz dr6eThe image is 38.6 cm tall, and 14.8 cm from the mirror. How far q:k fz9wn6 )rqgede 5d;1o0yj is the object from the mirror?

A. $124 \; cm$

B. $47.6 \; cm$

C. $18.2 \; cm$

D. $12.0 \; cm$

绑定到本题的附件链接:
绑定到本题的上传图片:

参考答案:

进入本题讨论区，参与讨论

本习题练习全部题目来源于51fly国际课程 (https://51fly.win)，学生可自助刷题练习，扫右侧二维码加微信，获取学习资料，答疑辅导
教师可以抽题组卷或一键复制他人试卷，布置为在线考试或在线作业，全自动判分成绩一键排序导出，省时省力

标记此题

81#

单选题 ( 1.0 分) 切至整卷模式搜藏此题

A 1.4 cm tall object is 4.00 0txdoi wx4.l cm from a concave mirror. If the image is 4.0 cm tallo4xdtxw l00i ., how far is it from the mirror?

A. $11 \; cm$

B. $9.4 \; cm$

C. $1.4 \; cm$

D. $0.090 \; cm$

绑定到本题的附件链接:
绑定到本题的上传图片:

参考答案:

进入本题讨论区，参与讨论

标记此题

82#

单选题 ( 1.0 分) 切至整卷模式搜藏此题

An object is placed 15 cm ty3 un u94gk; ud (t/fz1uio2wfrom a concave mirror of focal length 20 cm. The object is 41utw2;ki/duf 4z9( y guut 3on.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

绑定到本题的附件链接:
绑定到本题的上传图片:

参考答案:

进入本题讨论区，参与讨论

本习题练习全部题目来源于51fly国际课程 (https://51fly.win)，学生可自助刷题练习，扫右侧二维码加微信，获取学习资料，答疑辅导
教师可以抽题组卷或一键复制他人试卷，布置为在线考试或在线作业，全自动判分成绩一键排序导出，省时省力

标记此题

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 (concaveb2v-0ihh2 k ;b0uy )/pq3wl9 amrg aua mirror), the erect imag m00hlu2/ qk3w-a2hyra; abbv9pu gi )e is twice the size of the object. What is the focal length of the mirror?

A. $27 \; cm$

B. $40 \; cm$

C. $80 \; cm$

D. $160 \; cm$

绑定到本题的附件链接:
绑定到本题的上传图片:

参考答案:

进入本题讨论区，参与讨论

标记此题

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 z* 0xwa))3vmpryxr k18mk1v b a concave shaving mirror. If the image is an erect image 1.pa)1)kzw1*bmm3vxr 8 kv0 ryx5 times as large as the object, what is the mirror's focal length?

A. $20 \; cm$

B. $50 \; cm$

C. $70 \; cm$

D. $90 \; cm$

绑定到本题的附件链接:
绑定到本题的上传图片:

参考答案:

进入本题讨论区，参与讨论

标记此题

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 cwjnd+xc 4yl + 67hv4efocal length 5.0 cm. Where is the object?dc4+nl +j7 wvce y64hx

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

绑定到本题的附件链接:
绑定到本题的上传图片:

参考答案:

进入本题讨论区，参与讨论

本习题练习全部题目来源于51fly国际课程 (https://51fly.win)，学生可自助刷题练习，扫右侧二维码加微信，获取学习资料，答疑辅导
教师可以抽题组卷或一键复制他人试卷，布置为在线考试或在线作业，全自动判分成绩一键排序导出，省时省力

标记此题

86#

单选题 ( 1.0 分) 切至整卷模式搜藏此题

A convex spherical mirror hzww0qfqf /n5s1 8a+if as a focal length of -20 cm. An object is placed 10 cm in front of th iqwwfazsnq185/f0f +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

绑定到本题的附件链接:
绑定到本题的上传图片:

参考答案:

进入本题讨论区，参与讨论

本习题练习全部题目来源于51fly国际课程 (https://51fly.win)，学生可自助刷题练习，扫右侧二维码加微信，获取学习资料，答疑辅导
教师可以抽题组卷或一键复制他人试卷，布置为在线考试或在线作业，全自动判分成绩一键排序导出，省时省力

标记此题

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 is pzindp9 g0/oq6 laced 30 cm in front of the mirror on the mirror's axis. Where is the imagp oi0z 6qn9/gde 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

绑定到本题的附件链接:
绑定到本题的上传图片:

参考答案:

进入本题讨论区，参与讨论

本习题练习全部题目来源于51fly国际课程 (https://51fly.win)，学生可自助刷题练习，扫右侧二维码加微信，获取学习资料，答疑辅导
教师可以抽题组卷或一键复制他人试卷，布置为在线考试或在线作业，全自动判分成绩一键排序导出，省时省力

标记此题

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 bevg:h gww znf9x:8er 5)hind the mirror. What is the focal lengtz v5 efgw: wh9)8xn:rgh of the mirror?

A. -4.1 cm

B. -8.2 cm

C. -9.9 cm

D. -20 cm

绑定到本题的附件链接:
绑定到本题的上传图片:

参考答案:

进入本题讨论区，参与讨论

标记此题

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 t*m9o- tz */o 9wgjjjizall, and 14.8 cm from a convex mirror. What is the mirror's focal lgw/*z9*oj im oz9 jt-jength?

A. -120 cm

B. -105 cm

C. -16.9 cm

D. -13.0 cm

绑定到本题的附件链接:
绑定到本题的上传图片:

参考答案:

进入本题讨论区，参与讨论

标记此题

90#

单选题 ( 1.0 分) 切至整卷模式搜藏此题

If a material has an indnuj5 +f.x npgi,u1vq 4bdlkws ve*5::ex of refraction of 1.50, what is the speed of light through it?kwx*5f bnd,5n. gqv:sp1 u:j4 vl iue+

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

绑定到本题的附件链接:
绑定到本题的上传图片:

参考答案:

进入本题讨论区，参与讨论

标记此题

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 at an angl.w:;c p.s4jurbae(m ve 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

绑定到本题的附件链接:
绑定到本题的上传图片:

参考答案:

进入本题讨论区，参与讨论

标记此题

92#

单选题 ( 1.0 分) 切至整卷模式搜藏此题

Light enters a substance from air at 2an8pswx 88djan 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

绑定到本题的附件链接:
绑定到本题的上传图片:

参考答案:

进入本题讨论区，参与讨论

标记此题

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 ray is at an angles d,dlsc(b24f 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. $12.7^{\circ}$

绑定到本题的附件链接:
绑定到本题的上传图片:

参考答案:

进入本题讨论区，参与讨论

本习题练习全部题目来源于51fly国际课程 (https://51fly.win)，学生可自助刷题练习，扫右侧二维码加微信，获取学习资料，答疑辅导
教师可以抽题组卷或一键复制他人试卷，布置为在线考试或在线作业，全自动判分成绩一键排序导出，省时省力

标记此题

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 a0g s9bo8n3pucnd evenly over the surface of w9pu8os cnb0g 3ater on a windless 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. $39^{\circ}$

绑定到本题的附件链接:
绑定到本题的上传图片:

参考答案:

进入本题讨论区，参与讨论

本习题练习全部题目来源于51fly国际课程 (https://51fly.win)，学生可自助刷题练习，扫右侧二维码加微信，获取学习资料，答疑辅导
教师可以抽题组卷或一键复制他人试卷，布置为在线考试或在线作业，全自动判分成绩一键排序导出，省时省力

标记此题

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 mu+b*6dk wzxm9w5 thh6 gst the diver shine a beam of light toward the surface in5wb6g+wkt hzhdxm *69 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. $90^{\circ}$

绑定到本题的附件链接:
绑定到本题的上传图片:

参考答案:

进入本题讨论区，参与讨论

本习题练习全部题目来源于51fly国际课程 (https://51fly.win)，学生可自助刷题练习，扫右侧二维码加微信，获取学习资料，答疑辅导
教师可以抽题组卷或一键复制他人试卷，布置为在线考试或在线作业，全自动判分成绩一键排序导出，省时省力

标记此题

96#

单选题 ( 1.0 分) 切至整卷模式搜藏此题

A beam of light, traveling in air,3y lt 3o(ruyq zv-wc*4 strikes a plate of transparent material at an angle of incidence o t(3zw4oq3y-r*l yuvc f $56.0^{\circ}$. 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

绑定到本题的附件链接:
绑定到本题的上传图片:

参考答案:

进入本题讨论区，参与讨论

本习题练习全部题目来源于51fly国际课程 (https://51fly.win)，学生可自助刷题练习，扫右侧二维码加微信，获取学习资料，答疑辅导
教师可以抽题组卷或一键复制他人试卷，布置为在线考试或在线作业，全自动判分成绩一键排序导出，省时省力

标记此题

97#

单选题 ( 1.0 分) 切至整卷模式搜藏此题

A beam of light traveling in air if/xzqf o/(:in-ael/xh ejs+1 w 9zc)ns incident on a slab of transparent material. The incident beam and the refracted beam make angles on+9q ze/of x1(cfahwi)j nz/: xel/ -sf $40^{\circ}$ 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. $3.0 \times 10^{8} \; m/s$

绑定到本题的附件链接:
绑定到本题的上传图片:

参考答案:

进入本题讨论区，参与讨论

标记此题

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 ij iun rwz+5/e0s passing through it at uize0/rjw5+n $53.0^{\circ}$. At what angle will it leave into the air?

A. It will not leave.

B. $59.1^{\circ}$

C. $43.2^{\circ}$

D. $33.2^{\circ}$

绑定到本题的附件链接:
绑定到本题的上传图片:

参考答案:

进入本题讨论区，参与讨论

本习题练习全部题目来源于51fly国际课程 (https://51fly.win)，学生可自助刷题练习，扫右侧二维码加微信，获取学习资料，答疑辅导
教师可以抽题组卷或一键复制他人试卷，布置为在线考试或在线作业，全自动判分成绩一键排序导出，省时省力

标记此题

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 gla5w(zr;gt px7s p y.6ufss (n = 1.52) into water (n = 1.t;z 7p.g r6px5(wsyu f33)?

A. $42^{\circ}$

B. $48^{\circ}$

C. $57^{\circ}$

D. $61^{\circ}$

绑定到本题的附件链接:
绑定到本题的上传图片:

参考答案:

进入本题讨论区，参与讨论

标记此题

100#

单选题 ( 1.0 分) 切至整卷模式搜藏此题

Lucite has an index of refrz*m-n*oc b- lit s91olaction of 1.50. What is its critical angle of incidence c-oilb t-mlnz9s 1**o?

A. $11.6^{\circ}$

B. $15.4^{\circ}$

C. $41.8^{\circ}$

D. $87.4^{\circ}$

绑定到本题的附件链接:
绑定到本题的上传图片:

参考答案:

进入本题讨论区，参与讨论

标记此题

101#

单选题 ( 1.0 分) 切至整卷模式搜藏此题

An optic fiber is made of l20f +uim:y4gp l vxd5clear plastic with index of refraction of 1.50. For what angle of incidence will light remain within the plastic "guy+ 2l: gfpl d05mui4vxide"?

A. $>23.4^{\circ}$

B. $>38.3^{\circ}$

C. $>40.3^{\circ}$

D. $>41.8^{\circ}$

绑定到本题的附件链接:
绑定到本题的上传图片:

参考答案:

进入本题讨论区，参与讨论

标记此题

102#

单选题 ( 1.0 分) 切至整卷模式搜藏此题

The critical angle for0i 6nlx1kb3t r a substance 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.

绑定到本题的附件链接:
绑定到本题的上传图片:

参考答案:

进入本题讨论区，参与讨论

标记此题

103#

单选题 ( 1.0 分) 切至整卷模式搜藏此题

Light enters a substance from air at4 3 arqjvz2heg)m7ha, $30.0^{\circ}$ 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. $12.6^{\circ}$

绑定到本题的附件链接:
绑定到本题的上传图片:

参考答案:

进入本题讨论区，参与讨论

标记此题

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 d2bdcg4,. gou- bbgon6iameter 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 enteringb.cd2- bu g64no bg,go one end will make before it emerges from the other end?

A. 42,000

B. 26,000

C. 24,000

D. 18,000

绑定到本题的附件链接:
绑定到本题的上传图片:

参考答案:

进入本题讨论区，参与讨论

本习题练习全部题目来源于51fly国际课程 (https://51fly.win)，学生可自助刷题练习，扫右侧二维码加微信，获取学习资料，答疑辅导
教师可以抽题组卷或一键复制他人试卷，布置为在线考试或在线作业，全自动判分成绩一键排序导出，省时省力

标记此题

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 s,kr8wapd;ud/kw 1 d (20 cm focal length converging lens. How far is t/k;d8kur,ap ds dw1 (whe image of this object from the lens?

A. $40 \; cm$

B. $20 \; cm$

C. $13 \; cm$

D. none of the given answers

绑定到本题的附件链接:
绑定到本题的上传图片:

参考答案:

进入本题讨论区，参与讨论

本习题练习全部题目来源于51fly国际课程 (https://51fly.win)，学生可自助刷题练习，扫右侧二维码加微信，获取学习资料，答疑辅导
教师可以抽题组卷或一键复制他人试卷，布置为在线考试或在线作业，全自动判分成绩一键排序导出，省时省力

标记此题

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 focal length 4 cm. ynebb6xl29t p)74qqe Where il9bxnbeq)y6 2 7qep4t s 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

绑定到本题的附件链接:
绑定到本题的上传图片:

参考答案:

进入本题讨论区，参与讨论

标记此题

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 lens, avl.exhjw61a m; nqd 06nd the image is 4.0 mm behind the lens. What is the focal len0.en 6ah 6q;j md1xwvlgth of the lens?

A. $11 \; mm$

B. $5.5 \; mm$

C. $3.8 \; mm$

D. $3.2 \; mm$

绑定到本题的附件链接:
绑定到本题的上传图片:

参考答案:

进入本题讨论区，参与讨论

本习题练习全部题目来源于51fly国际课程 (https://51fly.win)，学生可自助刷题练习，扫右侧二维码加微信，获取学习资料，答疑辅导
教师可以抽题组卷或一键复制他人试卷，布置为在线考试或在线作业，全自动判分成绩一键排序导出，省时省力

标记此题

108#

单选题 ( 1.0 分) 切至整卷模式搜藏此题

A 14-mm tall object is 4.0lutgy5k p.; ,jf :ro-u mm from a converging lens. If the image is 4.0 mm tall, how far is ittpofkg .jl,r yu:u-5 ; from the lens?

A. $14 \; mm$

B. $8.7 \; mm$

C. $1.4 \; mm$

D. $1.1 \; mm$

绑定到本题的附件链接:
绑定到本题的上传图片:

参考答案:

进入本题讨论区，参与讨论

本习题练习全部题目来源于51fly国际课程 (https://51fly.win)，学生可自助刷题练习，扫右侧二维码加微信，获取学习资料，答疑辅导
教师可以抽题组卷或一键复制他人试卷，布置为在线考试或在线作业，全自动判分成绩一键排序导出，省时省力

标记此题

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 converginy +p0*cglk.ii2z)x*o qj3 w zgg lens the inverted image is half the size of the object. What is the focal length of thi)p2x i .z0l* gyg*cqwk zo3j+is lens?

A. $13 \; cm$

B. $20 \; cm$

C. $40 \; cm$

D. $53 \; cm$

绑定到本题的附件链接:
绑定到本题的上传图片:

参考答案:

进入本题讨论区，参与讨论

标记此题

110#

单选题 ( 1.0 分) 切至整卷模式搜藏此题

An image is 4.0 mm in fg5(cdvz-pxn9yyb7( 7ai3n na :+x uehront of a converging lens with focal length 5.0 mm. Where is the o gx(y7z 3:9(h7nxbe dnuvc+iy 5a-p anbject?

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

绑定到本题的附件链接:
绑定到本题的上传图片:

参考答案:

进入本题讨论区，参与讨论

本习题练习全部题目来源于51fly国际课程 (https://51fly.win)，学生可自助刷题练习，扫右侧二维码加微信，获取学习资料，答疑辅导
教师可以抽题组卷或一键复制他人试卷，布置为在线考试或在线作业，全自动判分成绩一键排序导出，省时省力

标记此题

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. The image is virt,k 2ipcj6+9txlzbv pvw00dz /ual and 6.2 cm tall. What is tv02itj/0c b,xwkv zplp9z+d 6he focal length of the lens?

A. $6.8 \; cm$

B. $10 \; cm$

C. $16 \; cm$

D. $30 \; cm$

绑定到本题的附件链接:
绑定到本题的上传图片:

参考答案:

进入本题讨论区，参与讨论

本习题练习全部题目来源于51fly国际课程 (https://51fly.win)，学生可自助刷题练习，扫右侧二维码加微信，获取学习资料，答疑辅导
教师可以抽题组卷或一键复制他人试卷，布置为在线考试或在线作业，全自动判分成绩一键排序导出，省时省力

标记此题

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. T 6-8i+xcex2pwei8g . d ;dhsuehe image is 4.0 mm tall, and 9.0 cm from thcewep8id8e-is h;d .+6xxgu2e lens. How tall is the object?

A. $6.8 \; mm$

B. $5.4 \; mm$

C. $1.7 \; mm$

D. $0.68 \; mm$

绑定到本题的附件链接:
绑定到本题的上传图片:

参考答案:

进入本题讨论区，参与讨论

标记此题

113#

单选题 ( 1.0 分) 切至整卷模式搜藏此题

When an object is placed 60 cm fx/er0suuqw, hyke 6-hw lb2(7 rom a converging lens, it forms a real image. When the object i ue(-/6qh7kluwyerb hs ,x0w2s 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. $42 \; cm$

绑定到本题的附件链接:
绑定到本题的上传图片:

参考答案:

进入本题讨论区，参与讨论

标记此题

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 3k16brl1 it a+fp6l e5ef:1l sb0 cm from a thin convex lens. The lens has a focal length of 10 cm. What are the values, respectively, of the image distance iba: bf66l1plfk+sle15re t 1and lateral magnification?

A. 15 cm, 2.0

B. 25 cm, 1.0

C. 60 cm, -0.50

D. 15 cm, -0.50

绑定到本题的附件链接:
绑定到本题的上传图片:

参考答案:

进入本题讨论区，参与讨论

标记此题

115#

单选题 ( 1.0 分) 切至整卷模式搜藏此题

An object is placed a+4(o eo:3zzm) mlqdfco0cf/jjt70tbt 30 cm in front of a diverging lens with a focal length of 1040o motfj / co7jt :lqbcz3ed (zm0f)+ cm. What is the image distance?

A. $7.5 \; cm$

B. $-7.5 \; cm$

C. $15 \; cm$

D. $-15 \; cm$

绑定到本题的附件链接:
绑定到本题的上传图片:

参考答案:

进入本题讨论区，参与讨论

标记此题

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 + fb6ok1ibs .*n ep; p8ets7hua diverging lens with a focal length of 10 cm. What is the mehukipf8 + nobt6ssp*eb.1 ;7agnification?

A. 0.25

B. -0.25

C. 0.67

D. -0.67

绑定到本题的附件链接:
绑定到本题的上传图片:

参考答案:

进入本题讨论区，参与讨论

标记此题

117#

单选题 ( 1.0 分) 切至整卷模式搜藏此题

An object is 10.4 cm tall,+x-.;znddlpe g( e-f sel k38i and 4.8 cm in front of a diverging lens. The image is 4.0 cm from the lens. How t. z ixed8kee--f3+( glpn ;dslall is the image?

A. $13 \; cm$

B. $8.7 \; cm$

C. $5.4 \; cm$

D. $1.8 \; cm$

绑定到本题的附件链接:
绑定到本题的上传图片:

参考答案:

进入本题讨论区，参与讨论

标记此题

118#

单选题 ( 1.0 分) 切至整卷模式搜藏此题

An object is 6.0 cm tall, prdeh gias-0 tz;/x h57;uad+ and is in front of a diverging lens. The image is 2.5 cm td-/t+i pa;;h0 rgxaz57h des uall, and 7.5 cm from the lens. What is the focal length of the lens?

A. -6.0 cm

B. -7.5 cm

C. -13 cm

D. -18 cm

绑定到本题的附件链接:
绑定到本题的上传图片:

参考答案:

进入本题讨论区，参与讨论

标记此题

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 frlhp*p.z3 y/wl om a thin lens. If a virtual image forms at a distance of 50 cm from thezplwy.l h /*3p 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. $200 \; cm$

绑定到本题的附件链接:
绑定到本题的上传图片:

参考答案:

进入本题讨论区，参与讨论

标记此题

120#

单选题 ( 1.0 分) 切至整卷模式搜藏此题

How far from a lens yfvuxi70m )p xs/6*ubkt 9xr zoi: -9uof focal length 50 mm must the object be placed if it is to for9o/ ruvi*sixxkzutm uf-p6: y) b09 7xm a virtual image magnified in size by a factor of three?

A. $33 \; mm$

B. $42 \; mm$

C. $48 \; mm$

D. $54 \; mm$

绑定到本题的附件链接:
绑定到本题的上传图片:

参考答案:

进入本题讨论区，参与讨论

标记此题

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 gd 0ivqy)jl0q:zb1q .used in many 35-mm cameras, must an object be positioned if it is to form a real image magnified ig:1l yb0q d)jq0qivz .n size by a factor of three?

A. $46 \; mm$

B. $52 \; mm$

C. $58 \; mm$

D. $67 \; mm$

绑定到本题的附件链接:
绑定到本题的上传图片:

参考答案:

进入本题讨论区，参与讨论

标记此题

122#

单选题 ( 1.0 分) 切至整卷模式搜藏此题

Two very thin lenses, each wi h)*a5(krc wvn 6cj8 v7rikh+tth focal length 20 cm, are placed in contact. What is the +w(7*)j8ckc ahvrik5nt rv 6 hfocal length of this compound lens?

A. $40 \; cm$

B. $20 \; cm$

C. $15 \; cm$

D. $10 \; cm$

绑定到本题的附件链接:
绑定到本题的上传图片:

参考答案:

进入本题讨论区，参与讨论

标记此题

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 curvature 46 cm, and imaia2ybg+ e*i0 eh7tc0w8 p .bs made of gla0ic +hye*i80mbt p7.be 2 gwaass of index of refraction n = 1.60. What is the focal length?

A. infinite

B. $38 \; cm$

C. $30 \; cm$

D. $18 \; cm$

绑定到本题的附件链接:
绑定到本题的上传图片:

参考答案:

进入本题讨论区，参与讨论

标记此题

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*rulp 9w:y 43jpweznrf)w . 4z) has a radius of 40 cm on the front side and 30 cm on zpl*4zfpn4 w9wyu3) re : wr.jthe back side. What is the focal length of the lens?

A. $11 \; cm$

B. $34 \; cm$

C. $80 \; cm$

D. $240 \; cm$

绑定到本题的附件链接:
绑定到本题的上传图片:

参考答案:

进入本题讨论区，参与讨论

标记此题

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 piel(c bfvb ).,9me.meh bce of plastic (n = 1.70). The radius of the front surface is 20 cm and the radius of the back surface is me 9(..b,ehlb) mvfb c30 cm. What is the focal length of the lens?

A. $17 \; cm$

B. $86 \; cm$

C. $-86 \; cm$

D. $-17 \; cm$

绑定到本题的附件链接:
绑定到本题的上传图片:

参考答案:

进入本题讨论区，参与讨论

标记此题

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 .ywv:we j(p/k. p;gh zlength of 40 cm. It is made of glass of index ofvwh/.:kpg (zjypwe ;. refraction
1.65. What radius of curvature is required?

A. $13 \; cm$

B. $26 \; cm$

C. $32 \; cm$

D. $36 \; cm$

绑定到本题的附件链接:
绑定到本题的上传图片:

参考答案:

进入本题讨论区，参与讨论

账号		自动登录	找回密码
密码			立即注册

网页聊天 (离线可收发)

加微信咨询 (申请一对一课程辅导，加本站学习交流群）

电话咨询：

发帖咨询：

查看帮助：

未使用图片

本次作答已使用

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

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

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