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Physics Problems of Grade 8 20 1 165438 68 Volume Compilation of Physics Zhenti of National Senior High School Entrance Examination: Light Phenomenon.

10.(20 1 1 Shenyang) There is a wonderful music fountain in the beautiful city square. The light beam from the bottom of the pool will illuminate the fountain with beautiful music. At a certain moment, a beam of light obliquely enters the air from the bottom of the pool through the water surface, and the light is reflected and refracted on the water surface. If the incident angle is 30o and the reflection angle is _ _ _ _ _ _ _ _; When the incident light is far away from the water surface, the refracted light will _ _ _ _ _ the water surface. 30 degrees from ...

1.(20 1 1 Shenyang) The following phenomena can be explained by the refraction of light: (a)

A. The bottom of the swimming pool is shallower than it actually is.

B. Seeing people's shadows under street lamps at night

C. see a wider range behind the car through the rearview mirror.

D at noon on a sunny summer day, I saw a round spot under the tree.

22.(20 1 1 Shenyang) (4 points) In the experiment of exploring the imaging law of convex lens, put the candle, convex lens with focal length equal to 10cm and light screen on the optical experimental platform, as shown in figure 10, adjust the centers of the candle flame, convex lens and light screen at the same height, and set the.

(1) Put the candle at point A and the light screen at point B. In order to find a clear image, the light screen should be moved to _ _ _ _ (fill in "left" or "right").

(2) Change the position of candles in turn and move the light screen until a clear image is found. The recorded data are as follows.

Multiplied by 1 234 56

Object distance (cm) 40 35 30 25 20 15

Image distance (cm)13.5141516.7 20 30

(1) In the 1-4 experiment, the image was inverted and _ _ _ _ _ _ _.

② The image of the 6th time is better than that of the 5th time (fill in "big" or "small").

(3) Put the candle at point C, and after observing the vertical magnified virtual image of the candle flame, if you want to see a larger virtual image, you should move the candle to _ _ _ _ _ (fill in "left" or "right").

(1) left (2), reduced (3), left

(20 1 1 Shaanxi) The statement about optical components is correct.

The lenses of myopia glasses are concave lenses.

A convex lens has a divergent effect on light.

Light does not deflect when it passes through a prism.

A plane mirror can't change the direction of light propagation.

Answer a

Analytic convex lens can condense light, and option B is wrong; When the light passes through the prism, it deflects, and option C is wrong; A plane mirror can change the propagation direction of light, but it cannot change the properties of light beam. Option d is wrong.

15, (20 1 1 Tianjin) Xiao Gang, whose height is 1.75m, is standing in front of a vertical plane mirror, and his image in the mirror is m away from him. If he moves 0.5m to the mirror, his image height is 1.75m (choose "greater than", "less than" or "equal to").

3 equals

6.(20 1 1 Tianjin) A student summed up three experimental conclusions as shown in table 1 when exploring the "convex lens imaging law", of which the correct one is (a).

I. Experiment 1

Experiment 2

C, experiment 3

D. Experiment 2 and Experiment 3

2.(20 1 1 Tianjin) At night, when the lights of the car shine on the taillights of the bicycle, the driver sees the taillights.

You can avoid reflected light in time. Fig. 2 The light path diagram of bicycle taillights is positive.

Indeed (a)

10, (20 1 1 Jilin) Figure 3 is a small light bulb used in a miniature flashlight, and the front of the small light bulb is equivalent to having an effect on light. Convex lens convergence

3.(20 1 1 Jilin) As shown in figure 1, the left scene is photographed with a camera, and the image formed on the negative is correct (b).

2 1, (20 1 1 Chifeng city) (6 points) Read the written materials and complete the following questions:

The length of the focal length f of the lens indicates the refractive power, and the shorter the focal length, the greater the refractive power. Usually, the reciprocal of the focal length of a lens is called the power of the lens, which is expressed by φ, that is, φ =1/f.

If the focal length of a lens is 0.5m, its power is φ = 1/0.5m = 2m- 1.

Usually, the lens power of glasses is the value of lens power multiplied by 100. For example, the lens angle of a 400-degree hyperopia lens is 4m- 1,

Its focal length is 0.25 meters.

Note: The power of convex lens (hyperopia lens) is positive, and that of concave lens (myopia lens) is negative.

(1) As shown in Figure 15, Xiaoming's eyes are imaged when he looks at objects, and his eye diseases need to be corrected.

The lens is ()

A, myopia convex lens B, myopia concave lens

C, hyperopic convex lens D, hyperopic concave lens

(2) If the focal length of the glasses he wears is 0.2m, the power of the glasses is m- 1.

Degree is degree.

( 1)、B (2)、5 -500

2. (20 1 1 Chifeng City) The following correlation is correct (D)

A, the straight-line propagation of light-insert the pencil obliquely into a glass filled with water, as if it were broken.

B, light refraction-the trees on the shore are reflected in the water.

C, the reflection of light-the formation of shadows

D, light reflection-people can see their own image in the mirror.

20.(20 1 1 Liuzhou) After the sunlight passes through the prism, it is decomposed into various colors of light, which is the _ _ _ _ _ _ _ phenomenon of light. As shown in Figure 6, when a pencil is inserted obliquely in a glass filled with water, it seems that the pencil is broken on the water core. This phenomenon is caused by _ _ _ _ _ _ _ _ _ _. 20, dispersion (refraction), refraction

9.(20 1 1 Liuzhou) Among the following items, A is not applicable to the principle of convex lens imaging.

A. Mirror B. Projector C. Camera D. Magnifier

5.(20 1 1 Liuzhou) A classmate is standing in front of the plane mirror at 1 m, and the image in the mirror is far from the plane mirror D.

A.0m B.0.5 C.0.8 D. 1 m

26.(20 1 1 Dazhou) Every morning when you walk into the plastic surgery mirror with a smile at the speed of 1m/s, your image in the mirror approaches you at the speed of m/s, and the size of your image in the mirror (fill in "bigger", "smaller" or "unchanged"

26, 2 unchanged

10.(20 1 1 Dazhou) Divers dived into the water and saw the treetops on the shore become higher. Of the four optical paths shown below, which one can correctly explain this phenomenon: C.

28.(20 1 1 Jixi) What factors are related to the size of convex lens imaging in experiments?

(1) Wu Yang knows that a magnifying glass is a convex lens through the study of physical knowledge. In the activity class, he observed his finger with a magnifying glass (as shown in Figure A) and saw the image of his finger. Then use a magnifying glass to observe the distant house (as shown in Figure B) and see the image of the house. (Select Enlarge, Equal Size or Reduce)

(2) He guessed that the size of the convex lens imaging may be related to the distance from the candle to the lens. So, he kept changing the distance from the candle to the lens on the light table shown in figure C, and moved the light curtain to carry out the experiment. The experimental data obtained are shown in the following table:

opposition

Distance of convex lens/cm image on screen

Distance of convex lens on screen/cm

Image size

3.00 There is no image on the screen.

5.00 There is no image on the screen.

12.00 60.00 magnification

20.00 20.00, etc.

25.00 16.67 reduction

30.00 15.00 reduction

According to the analysis data, the longer the distance from the object to the convex lens, the larger the image on the screen.

(3) When Wu Yang was filming graduation photo, the photographer found that there were still students on both sides who were not in the frame. The photographer should keep the camera away from the students, and at the same time (choose "increase", "shorten" or "don't change") the length of the camera's black box to get a clear and satisfactory picture.

28.(65438+ 0 point per grid)

(1) Zoom in and out

(2) Small

(3) Shortening

2 1.(20 1 1 Jixi) Students study very hard, and many students' eyesight has changed, which affects their study life and needs to be corrected. Please choose correctly from the following two pictures: the one that corrects myopia is; What corrects hyperopia is. (Select "A" or "B")

2 1.

3.(20 1 1 Jixi) In the phenomenon shown in the figure, (a) belongs to the reflection of light.

24(20 1 1 Putian), (5 points) As shown in the figure, when a classmate is doing the experiment of "exploring the imaging characteristics of flat mirror", he vertically puts a glass plate on a ruler, takes two identical candles A and B, and vertically stands A and B in tandem on the ruler. During the experiment, the eyes are always on the side of candle A.

(1) Light candle A and adjust the position of candle B. When it is, the position of candle B is the position of the image of A. ..

(2) In the experiment, the ruler is used to compare the relationship between images and objects; Like two candles, it is to compare the relationship between things and objects.

(3) Using a flat mirror instead of a glass plate to carry out the above experiment (fill in "can" or "can't") is because.

4.(20 1 1 Putian) Among the following phenomena, (c) belongs to the straight-line propagation of light.

A, there is a big mirror on the wall, which has the feeling of increasing space.

B, the clear river bottom looks very shallow.

C, a person walking under a street lamp, a figure.

D, early in the morning, when the sun is still below the horizon, you can see it.

16, (20 1 1 Zigong) A beam of light is reflected on a flat mirror. If the reflection angle is 30 and the incident angle is b.

a、0； b、30； c、45； d、90 .

18, (20 1 1 Zigong) The distance from the lens of many cameras to the film is adjustable. The photographer has "adjusted the focal length" before a certain shooting, so that the subject can form a clear image on the film. If the distance between the subject and the photographer becomes longer before shooting, the distance between the lens and the film should be a in order to make him still a clear image on the film.

A, smaller; B, get bigger; C, first getting smaller and then getting bigger; D, first get bigger and then get smaller.

37, (20 1 1 Zigong) Xiao Ming looked at the calm lake, and the fish swam around in the white clouds. The fish he saw was a virtual image formed by _ _ _ _ of light; If the water depth in the lake is 3m, the distance from the image formed by white clouds to the water surface _ _ _ _ _ _ _ _ _ 3m. (optional "greater than", "less than" or "equal to") Fold greater than

19, (20 1 1) (6 points) (1) Xiao Qiang did a dispersion experiment of light, and saw that red, orange, yellow, green, blue, indigo and purple bands appeared on the screen after white light was refracted by a prism, resulting in a problem: red light. So he used red light and purple light to inject into the main optical axis of the same convex lens in parallel to verify it.

A please draw the red light and purple light refracted by a convex lens in figure 12 (F 1 and F2 in the figure indicate the focus).

B. Xiao Qiang concluded that:

(2) As shown in figure 13, Xiaoli explores the imaging law of convex lens. Properly move the position of the candle and lens on the optical bench to obtain a reduced image on the optical screen; Keep the position of the candle and the light screen unchanged, and move the lens to get an enlarged image on the light screen; Then, the candle and the lens are kept in the same position, and the original lens is replaced by a convex lens with a smaller focal length for experiments, and a clear image can be obtained by moving the screen. At this time, the size of the image has changed compared with that before replacing the lens.

10, (20 1 1) Put an object at a distance of 20 cm from the convex lens, and at a distance of 6 cm from the convex lens on the other side, a clear image appears on the screen. Then the focal length of the lens can be (b)

3 cm, 5 cm, 7 cm, 9 cm

6.(20 1 1) Regarding the light phenomenon, the following statement is correct (D).

A. When people are far away from the plane mirror, the image in the plane mirror becomes smaller and smaller.

B. The image of an object passing through a small hole is an upright and reduced real image.

C. When light enters the water from the air, its propagation direction will inevitably change.

D. The hollow bubbles in Figure 3 have divergent effect on the incident parallel light.

48.(20 1 1 Harbin) (2 points) The incident light and the outgoing light are as shown in the figure, indicating that the optical elements in the box have an influence on the light. Please draw the elements in the box. Convergence.

42.(20 1 1 Harbin) (2 points) A flat mirror was erected in the school lobby. When students approach the mirror, they see the size of their own image in the mirror (choose "bigger", "smaller" or "unchanged"); Two students standing in front of the mirror can see each other's faces through the mirror, indicating that the optical path is _ _ _ _ _ _ _.

Invariant reversible

25.(20 1 1 Harbin) Xiao Ming observed the words in the book twice with a convex lens and saw two scenes as shown. The following statement is correct (c).

A. Figure A shows the real image; What is formed in Figure B is a virtual image.

B. The book in Figure A shows the focal length of a convex lens twice; The book in Figure B is within l times the focal length of the convex lens.

C. In Figure A, the convex lens is close to the book, and the image becomes smaller; In figure B, the convex lens is far away from the book, and the image becomes smaller.

D. the imaging rule in fig. a can be applied to a projector; The imaging law in Figure B can be applied to cameras.

25.(20 1 1 Yantai) Figure 18A shows Xiaohong's experimental device of "exploring flat mirror imaging", in which A and B are two identical candles, C is flat white paper and E is glass plate.

(1) Place the lighted candle A in front of the glass plate, and observe the image of the candle A' behind the glass plate. At this time, the candle B is moved behind the glass plate to completely coincide with the image A'. But no matter how Xiaohong moves B, she can't completely coincide with the image A' of the candle. What do you think may be the reason for this?

(2) After finding the problem and improving it, Xiaohong did another experiment, and recorded the position of the object corresponding to the image after many experiments on white paper, as shown in figure 18B. Please write down how to analyze and process the information recorded in the laboratory before reaching the experimental conclusion.

6.(20 1 1 Lishui) Among the light phenomena shown in the figure, A belongs to the phenomenon of straight-line light propagation.

3 1.(20 1 1 Beijing) Xiaohua wants to explore the imaging law of convex lens. There are three convex lenses a, b and c on the experimental platform, in which the focal length of convex lens a

Is 10cm, the focal length of convex lens B is 50cm, and the focal length of convex lens C is unknown. The scale range of the scale on the optical platform is shown in Figure 15.

(1) Xiaohua should choose a convex lens (choose "a" or "b") in order to explore the law of convex lens forming real images. experiment

In this process, when he placed the lighted candle 25 cm away from the convex lens, he moved the light screen until it appeared on the light screen.

If there is a clear candle flame image, it should be an inverted real image. (You can choose "Zoom in" or "Zoom out")

(2) Xiaohua fixes the convex lens C at the score line of 50cm on the optical bench, when the candle flame engraves 30cm to 40cm on the optical bench.

Between the lines, the image of candlelight is an enlarged and inverted real image; When the candle flame is scratched from 0 cm to 30 cm on the optical bench.

Sometimes, the image of candle flame is a real image of shrinking and upside down. It can be judged that when the candle flame is at the 45cm mark on the optical bench,

The image of candle flame is enlarged and lifelike.

3 1.( 1) Decrease

(2) Right and False

20.(20 1 1 Beijing) White light is refracted by a prism and irradiated on a light screen, forming a light band composed of red, orange, yellow, green, blue, indigo and purple, indicating that white light is composed of light. colour

18.(20 1 1 Beijing) The lenses of myopia glasses are lenses. (optional "convex" or "concave") concave

2. Of the four phenomena shown in (20 11Beijing) Figure1,C belongs to the light reflection phenomenon.

37.(20 1 1 Shanxi) Xiaohao used the experimental equipment as shown in figure 10 to explore the "imaging characteristics of flat mirrors". Please help him complete the following questions:

(1) In order to facilitate observation, the experiment should be conducted in the environment (fill in "bright" or "dark");

(2) It is observed that candle A has two almost overlapping images behind the glass plate, which is caused by the following reasons:

(3) If the candle A is close to the glass plate, the size of the image will be reduced.

37.( 1) The dark glass plate (2) is thick.