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1. (Tianjin) A beam of light slanted into the water from the air. When the incident angle increases gradually, the refraction angle will be: ()

A. Constant B. Gradually decreasing

C. gradually increase, but always less than the incident angle d. Gradually increasing, possibly greater than the incident angle.

2. There are many sentences describing the phenomenon of light in Yancheng ancient poetry, such as "the water in the pool is shallow" and "the moon is reflected in the pool". These two poems describe light respectively: ()

A. reflection, reflection B. reflection, refraction C. refraction, reflection D. refraction, refraction

3. (Ningbo) The flame of the candle only gets an inverted enlarged image on the screen through the convex lens. If the position of the convex lens remains unchanged and the position of the candle flame and the screen is reversed, then: ()

A. You can still see an inverted enlarged image on the screen.

B. get an inverted and reduced image on the screen.

C. an upright magnified image can be observed through the lens.

D. There is no image on the light screen, and it is necessary to adjust the position of the light screen to image.

4. (Yantai City) When watching the waterscape photos, you will always find that the "reflection" of the scenery is darker than itself. This is because: ()

A. The definition of "reflection" is worse than the real scene. B. part of the light that people shoot at the water surface is refracted into the water.

C. some light is reflected. D. there is something wrong with the quality of the developed photos.

When the convex lens of Suzhou is facing the sunlight, the smallest and brightest spot can be obtained at the distance of 10cm from the convex lens. If you put an object on the main optical axis of this lens, 30cm away from the lens, you can get it on the other side of the lens: ()

A. The real image enlarged by handstand B. The real image reduced by handstand

C. vertically enlarge the virtual image D. vertically reduce the virtual image

6. (Henan Province) In the experiment of exploring the imaging law of convex lens, when the candle flame, convex lens and light screen are in the positions shown in the figure, a clear image can be obtained on the light screen. Using this imaging principle, it can be made as follows: ()

A. camera B. slide projector C. magnifying glass D. periscope

7. Regarding convex lens imaging, the following statement is correct: ()

A. when forming a real image, the image must be smaller than the object.

B. When forming a virtual image, the image must be larger than the object.

C. When forming a real image, images and objects must be on both sides of the lens.

D. When forming a virtual image, the image and the object must be on the same side of the lens.

8. When the object is away from the convex lens 20㎝ and a clear image is obtained on the screen at the other side 30㎝ of the convex lens, it should be: ()

A. enlarged B. reduced C. equal D. unable to judge

9.(03 Hohhot) The object is placed in front of the convex lens, and the distance to the convex lens is 16cm. At this time, the enlarged image is obtained on the screen, so the focal length of the lens used may be: ().

A.4cm.b.8cm.c.10cm.d.18cm

10. (Jingzhou, 03) When a classmate was doing the experiment of "observing convex lens imaging", he lit a candle and placed it at a distance of 15cm, and got a clear, inverted and enlarged candle flame image on the screen. When he moved the candle 7 cm away from the convex lens ()

A. You can still get an inverted and enlarged image by moving the screen. B. You can get an inverted and reduced image by moving the light screen.

C no matter how you move the screen, you can't see the image of the candle flame on the screen. D. Move the screen, and you can see an upright and enlarged image on the screen.

1 1. Xiaoli takes pictures of her distant classmates with her camera. The film she took is shown in Figure 3B. If the focal length of the camera remains the same, and if the image of the film is as shown in Figure 3A, then ().

A. Xiaoli is far away from the classmate being photographed, so the camera should be stretched forward.

B: Xiaoli is close to the classmate who was photographed. She should take her camera back.

C. Xiaoli is far away from the classmate who was photographed, and the camera should be taken back.

D. Xiaoli is close to the classmate being photographed, and the camera should be stretched forward.

12. When the relative positions of the screen, lens and candle flame are shown in Figure 8, Zhang Qiang can get a clear image on the screen. Judging from this, the focal length of his convex lens ().

A.it must be more than 20 cm.

B it must be between10cm and16cm.

C. it must be less than 8 cm.

D it must be between 8 cm and 10 cm.

13. When light is emitted from one medium to another, the following statement is true ().

A. refraction is bound to happen. B. When refraction occurs, the refraction angle must be less than the incident angle.

C. emission and refraction will not happen at the same time. D as long as you enter another medium, the speed of light will change.

14. In the experiment of studying the imaging of convex lens with candles, the focal length of convex lens is lOcm, the lighted candle is placed at a distance of 15cm, and a clear image of the candle is observed on the light screen on the other side of the convex lens. This image must be ()

A. Inverted magnified real image

C. Vertical magnified virtual image D. Vertical magnified real image

15. The four pictures in the picture are the imaging situation and correction exercise of myopia respectively ().

A.②① B.③① C.②④ D.③④

16. In the "convex lens imaging" experiment, when the distance from the candle flame to the lens is 20 cm, a reduced image is observed on the screen on the other side of the lens. If the candle flame is 0/5cm away from the lens/kloc-,then the candle flame passes through the lens on the screen ().

A. It must be a reduced real image B. It must be a constant real image C. It may be an enlarged real image D. It may be a virtual image.

17. When you take pictures of your classmates with a camera with the same focal length, a clear bust appears on the negative. If you want to take a full-length photo, you should ().

A. Keep the camera away from classmates and adjust the lens forward.

B. Keep the camera away from classmates and adjust the lens backwards.

C. the camera is close to the classmate and the camera is adjusted forward.

D. the camera is close to the classmate and the camera is adjusted backwards.

18. In the following cases, the refraction of light is ().

A, the sun shines on the dense leaves, and light spots appear on the ground.

B. Divers "overhead" underwater to see the scenery on the shore.

C people saw "white clouds" fluttering in the water by the lake.

D, I believe I can see the unlit desks and chairs from all directions.

19. When the object moves along the main optical axis of the convex lens and the object distance is 30 cm, an enlarged real image is obtained on the light screen on the other side of the convex lens. When an object moves to the object distance 15 cm, its image must be: ()

A, enlarge the real image; B, the reduced real image; C, enlarging the virtual image; D, reducing the virtual image

20. In the experiment of studying the imaging law of convex lens, no matter how Xiao Ming moves the screen, there is no clear candlelight image on the screen. The reason for this phenomenon may be (multiple choices) ().

A the centers of candles, convex lenses and light screens are not on the same horizontal line.

B, the distance between the candle and the convex lens is greater than the focal length.

C, the distance between the candle and the convex lens is less than the focal length.

D the distance between the candle and the convex lens is equal to the focal length.

2 1. As shown in the figure, OO' is the principal axis of the convex lens, and S' is the image formed by S through the convex lens. If the focal length of the convex lens is f, the object distance range is ().

A. less than one focal length B. between one focal length and two focal lengths

C. More than twice the focal length D. Unable to judge

22. As shown in the figure, the correct light path diagram through the lens is ().

23. The candle is placed on the main optical axis 20 cm away from the convex lens, and an enlarged image is obtained on the screen on the other side of the lens. If the candle moves 8 cm towards the lens, the image must be ().

A. Reduced B. Enlarged C. Upright D. Inverted

24. As shown in the figure, the light path diagram after the light passes through the lens is correct ()

As shown in Figure 6- 13, a pile of hay is piled under a plastic film roof. After the rain in summer, the sun shines brightly.

25. As shown in the figure, S is the luminous point on the main optical axis of the convex lens, and s a is the light it emits. After being refracted by a convex lens, it is correct to refract light ().

exchange; communicate

C.ad D. ae

26. Do the experiment of "studying convex lens imaging" on the optical bench. Keep the candle and the lens in the same position, light the candle and adjust the position of the light screen until a clear candle flame image appears on the light screen (as shown in the figure). Then the image observed on the screen is (the focal length of the convex lens is 10 cm) ().

27. As shown in the figure, a beam of light in the air enters a transparent medium and is reflected and refracted at the interface. It is reflected light, not refracted light.

28. Xiaogang took a beautiful picture at the bottom of a pool full of water with a well-adjusted camera. After draining the water in the pool, Xiao Gang wants to take a clear picture in the original position with this camera, so he has to adjust the camera to make the lens (fill in "stretch forward", "retract backward" or "don't move").

29. As shown in the figure, light is emitted from one medium to another, and MN is the interface between the two media. If a medium is air, the emission angle is _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _.

30. The phenomenon of light has been described in ancient China, such as "You can't catch the moon in the water,

What can't be picked is the flowers in the mirror and the water in the pool is clear and shallow. Among them, "Flowers in the Moon Mirror in Water"

It is formed by the _ _ _ _ _ _ _ _ phenomenon of light, and "suspected water is shallow" is light.

The phenomenon of _ _ _ _ _ _ _ _ _ _.

3 1.(04 Changsha) The lens of the camera is equivalent to a _ _ _ _ lens. When the focal length of the lens is 40cm and the distance between the subject and the lens is greater than _ _ _, an inverted reduced image can be formed on the film.

32. As shown in the figure, light enters from one medium to another, and MN enters the interface of the two media. If a medium is air, the incident angle is _ _ _ _ _ degrees, and the _ _ plane of MN is air (fill in "left" or "right").

33. In the experiment of "Studying the imaging conditions of convex lens", the focal length of convex lens is 10cm. When the candle flame is inverted and narrowed on the screen, the distance from the candle to the convex lens is greater than cm. When the distance between the candle and the convex lens is less than cm, an upright and enlarged virtual image can be seen through the convex lens.

34. (Weihai) In the phenomena of "A pinhole imaging, B hand shadow game, C mirage imaging and D magnifying glass imaging", the linear propagation law of light is _ _ _ _ _ _ _ _; Using the refraction of light imaging is _ _ _ _ _ _ _ _; Belong to the law of convex lens imaging is _ _ _ _ _ _ _. (Fill in the letter code)

35. A student in Guangdong Province observed stamps with a magnifying glass with a focal length of 15cm. The distance between the stamp and the magnifying glass should be _ _ _15cm (fill in "greater than", "less than" or "equal to"), and the generated image will be enlarged, _ _ _ _ _ (fill in "vertical"

36. (Suining City) The fish raised in the round fish tank looks bigger than the real fish. The reason is that the round fish tank is equivalent to a _ _ _ _ _, and the "fish" you see is the _ _ _ _ image of the fish.

37. Xiaohua (Huanggang City) visited the exhibition. In a small exhibition hall, she saw a female tour guide introducing goods. She tried to shake hands with her, only to find that she was a virtual tour guide, beyond her power. Later, he found that the female tour guide was just a processed image on an inverted TV screen behind a glass screen. Then the glass screen is a _ _ _ _ _ _ _ mirror, the virtual tour guide is a _ _ _ _ _ _ _ (fill in "virtual" and "real"), and the distance between the TV screen and the glass screen should meet the condition of _ _ _ _ _ _.

38. (Dalian) As shown in the figure, it is the experimental device diagram of "Studying the imaging law of convex lens". Put away the instrument, light the candle, and adjust the heights of _ _ _ _ _ _ _ _ _ and _ _ _ _ _ _ so that the center of the instrument and the center of the candle flame are approximately at the same height. The purpose of this is _ _ _ _ _ _ _. In the experiment, it was found that when the candle was placed in _ _ _ _ _ _ _ _, its image was in 2F. When it is placed in _ _ _ _ _ _, its image becomes a virtual image, and when it is placed in _ _ _ _ _ _, the virtual image is enlarged in an upright position.

39.(03 Yancheng) In the experiment of "observing convex lens imaging", three sliders A, B A.B.C on the optical bench are used to place convex lenses, light screens or candles (as shown in the figure), of which B should be placed _ _ _ _ _ _ _ _ _ _ _. After the equipment is installed, if a classmate fixes B in the experiment, no matter how to move A and C, no image can be found on the screen, then the reason is _ _ _ _ _ _ _ _ _.

40. Draw a suitable shot in the picture. Draw two rays refracted by a convex lens, as shown in the figure.

4 1. The figure shows the light emitted to the lens from two focal lengths and one focal length of the convex lens respectively. Please draw their optical paths after passing through the lens in the picture (P is the position where the distance from the lens is equal to twice the focal length).

42. In the upper right picture, A is the light emitted by the point light source S, and B is the light refracted by the lens from the point light source S. Please complete the light path diagram and determine the position of S. ..

43. As shown in the figure, F is the focus of the convex lens, L 1' and L2' are the incident rays L 1 and L2' are the emergent rays refracted by the lens, l 1' is parallel to the main optical axis, and L2' passes through the optical center O. Please draw the sum of the incident rays l 1 in the figure.

44. The picture at the top right shows two rays hitting a concave lens. Please draw the refracted rays of these two rays on the picture.

45. Please complete the light path diagram in Figure 18.

46. As shown in figures 10,1and 12, AO is the incident light and OB is the outgoing light after passing through the mirror. In the following three cases, the point o is used as a graph (three different types) to fill the appropriate mirror image.

47. Complete the following light path diagram:

48. As shown in the figure, a beam of light AO is reflected and refracted when it obliquely hits the water surface from the air, and its reflected light and refracted light are made in the figure.

49. Figure 5-5 shows the light path of oblique incidence from air to water. Please draw the position of interface and normal in Figure 5-5. (2 points)

49. Complete the light path in Figure 2 1.

5 1. In the experiment of exploring the imaging law of convex lens, the lighted candle, convex lens and light screen are placed on the same straight line A, O and B in turn.

Position, get a clear image of the candle flame on the light screen, as shown in the figure.

(1) Move the convex lens to _ _ _ _ _ _ _ _ to make the image of the candle flame clearly form in the center of the screen.

(2) At this time, the image is inverted, and the real image is _ _ _ _ _ _ _ _ _.

(3) Adjust the centers of the candle flame, the convex lens and the light screen at the same height, move the candle away from the convex lens for a certain distance, and adjust the light screen.

Bit to get a clear image. Compared with the original image, this image will be _ _ _ _ _ _ (fill in "bigger", "smaller" and "unchanged").

52. In the experiment to explore the law of convex lens imaging:

1 students put the lighted candle, lens and light screen on the optical bench in turn. However, no matter how you move the screen, you can't find a clear image in the experiment. Please help them find a possible reason: _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _.

65438 Team +0 Team 2

Focal length of convex lens/cm1414141616.

Object distance/cm 20 30 40 60 20 30 40 60

Image distance /cm 47 26 22 18 80 34 27 22

Inverted inverted inverted inverted inverted inverted inverted inverted inverted inverted inverted inverted inverted inverted inverted inverted inverted inverted inverted inverted inverted inverted inverted inverted inverted inverted inverted inverted inverted inverted inverted inverted inverted inverted inverted inverted inverted inverted inverted inverted inverted inverted inverted inverted inverted inverted inverted inverted inverted inverted inverted inverted inverted inverted inverted inverted inverted inverted inverted inverted

Please analyze the above data. What conclusion can you draw? (just write two)

( 1)_________________________________________________________________________

(2)_________________________________________________________________________

53. As shown in figure 1 1, the image A'B' formed on the main optical axis after the object AB passes through the convex lens on the light screen. Please draw the convex lens according to the conditions given in the figure and determine the position of the focus F (4 points).

54. As shown in the picture, a glass plate with parallel upper and lower surfaces and smooth grinding is laid flat on a wooden table. A beam of light enters the upper surface of the glass plate at an angle of 50 from the air. It is known that the refraction angle of light entering the glass plate is 30. Please draw all the reflected and refracted light of this beam on the upper and lower surfaces of the glass plate in the picture. (Note that the normal line is marked)

55. In the experiment of "observing convex lens imaging", during an imaging process, the image of candle flame B on screen C is as shown in the figure (A is convex lens in the figure). (1) Please draw the approximate position of candle B on the straight line below; (2) According to this imaging feature, people have made _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _

56. In the experiment of exploring the imaging law of convex lens, in order to get a clear image of candle flame on the light screen, the lighted candle, convex lens and light screen are placed on the same straight line, as shown in the figure.

(1) Move the convex lens to _ _ _ _ _, so that the image of the candle flame can be clearly formed in the center of the screen.

(2) at this time, the image is like an inverted, real _ _ _ _ _ image.

(3) Adjust the centers of the candle flame, the convex lens and the light screen to the same height, move the candle to the convex lens for a certain distance, and adjust the position of the light screen to obtain a clear image. Which one is _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _.

57. In the experiment to explore the law of convex lens imaging:

1 students put the lighted candle, lens and light screen on the optical bench in turn. However, no matter how you move the screen in the experiment, you can't find a clear image. Please help them find a possible reason.

The 1 and 2 experimental groups have performed several operations respectively, and the experimental data are accurately recorded in the following table.

Focal length of convex lens/cm

14

14

14

14

16

16

16

16

Distance from object to convex lens /cm 20 30 40 60 20 30 40 60

Distance from image to convex lens /cm 47 26 22 18 80 34 27 22

Inverted inverted inverted inverted inverted inverted inverted inverted inverted inverted inverted inverted inverted inverted inverted inverted inverted inverted inverted inverted inverted inverted inverted inverted inverted inverted inverted inverted inverted inverted inverted inverted inverted inverted inverted inverted inverted inverted inverted inverted inverted inverted inverted inverted inverted inverted inverted inverted inverted inverted inverted inverted inverted inverted inverted inverted inverted inverted inverted inverted

59. In the experiment of observing convex lens imaging, keep the position of convex lens unchanged and put the flame of candle on the point. A, B, C, D, E in turn, as shown in the figure, while adjusting the position of the light screen, and then

(1) When the candle flame is placed in _ _ _ _ _ _ _ _, the smallest image appears on the screen;

(2) Put the candle flame at the point of _ _ _ _ _ _, and the image on the screen will be the largest;

(3) Put the candle flame at the _ _ _ _ _ point, and the image of the candle flame will not appear on the screen;

(4) If the candle flame moves from point A to point D, the distance from the image to the convex lens is _ _ _ _ _, and the size of the image is _ _ _ _ _ _. (Fill in "bigger", "smaller" or "unchanged")

60.( 1) As shown in Figure 7, what are the visual problems of this eye?

(2) What lens should I wear to correct this eye? Why do you have to do this to make your eyes see things clearly?

6 1. The refracted ray of incident ray AO is roughly drawn, and the incident angle I and the refraction angle γ are marked.

62. As shown in Figure 6, a beam of light from the luminous point S is projected on the water surface, and one of the beams passes through the point A after reflection. Please make incident light, reflected light and roughly refracted light.

63. As shown in the figure, it is an experimental device diagram of Xiao Ming's exploration of "convex lens imaging law". Put away the instrument, light the candle, and adjust the height of _ _ _ _ _ _ _ _ _. The data he recorded in the experiment and the imaging situation he observed are as follows:

As can be seen from the table, the focal length f of the convex lens used by Xiao Ming is _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _.

Number of experiments Distance from candle to lens/Attribute of U image

Inverted or upright to enlarge or reduce.

1 8cm vertical magnification

2 18cm inverse amplification

3 30cm inverted reduction

64. Myopia is a common disease among teenagers. What is myopia? Students from an interest group in a school conducted the following inquiry experiments.

As shown in Figure A, myopia glasses are placed between a candle and a convex lens, so that a clear image is displayed on the light screen, and the position of the light screen is marked, indicating the position of the retina of the myope. Take away your glasses, and the image on the screen becomes blurred. Move the screen towards the lens, the image becomes clear again, and then mark the position of the screen. Observe the eyeball structure as shown in Figure B combined with the above experiment:

(1) Can you guess whether the lens in the eyeball is equivalent to _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _.

(2) When myopia patients don't wear glasses, the objects they see fall on _ _ _ _ _ _ _ _ _

(3) The glasses that should be worn to correct myopia are concave lenses, whose function is _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _.

65. After learning the contents of eyes and glasses, they want to explore the causes of myopia through experiments. They chose the following equipment: candles, water-filled convex lenses made of thin films (connected with syringes and containing a small amount of water), light shields and so on. The thickness of the water-filled convex lens can be adjusted by the amount of water injected and absorbed by the syringe. The device is shown in the figure. (5')

(1) In this experimental device, _ _ _ _ _ _ is equivalent to the lens in human eyeball. _ _ _ _ _ is equivalent to the retina in the human eye.

(2) Please use this experimental device to explore the causes of myopia and write the experimental process.

66. As shown in Figure (a), the straight line AB is the dividing line between the smooth wooden board and the cotton cloth (the wooden board and the cotton cloth are on the same horizontal plane), and then a small spool (such as the spool on a sewing machine) is allowed to roll at a constant speed along the PO direction at a certain angle to the straight line AB, so it can be seen that the rolling direction of the spool on the cotton cloth has changed. As shown in Figure (b), the propagation direction of a beam of light obliquely incident on the glass from the air has also changed. (6)

(1) As can be seen from Figure (a), when the first wheel of the bobbin just touches the cotton cloth, its speed will (decrease/keep constant/increase) and the speed of the second wheel will (decrease/keep constant/increase).

(2) From the two similar phenomena in Figure (a) and Figure (b), it can be seen that the reason why light is refracted when it obliquely enters the glass from the air may be .2'.

First, multiple-choice questions.

1. Some people have the following understandings of sound phenomenon, and the correct one is ().

A. the speed of sound is constant in all kinds of media. Sound travels at maximum speed in a vacuum.

C. air is the medium of sound. People speak by vibrating their tongues.

2. The following statement is true ()

A. The formation of "shadow" shows that light travels in a straight line in the same medium.

B. The closer a person is to a flat mirror, the bigger the image becomes.

C. the propagation speed of light in a vacuum is

D. diffuse reflection will occur when light shines on clothes.

3. The following statement about light phenomenon is correct ()

A. Both solar and lunar eclipses are caused by the linear propagation of light.

Plane mirror imaging is caused by the refraction of light.

C. The small fish in the water and the white clouds in the blue sky seen in the lake are all virtual images formed by the reflection of light.

D People see objects that do not emit light because the diffuse reflection on the surface of the object does not obey the law of light reflection.

Among the 24 solar terms, the sun shines vertically on the tropic of Capricorn only during the winter solstice. At noon from the winter solstice, if a straight pole with a length of 1m is vertically erected on the horizontal line in Beijing, its shadow should be (the latitude of Beijing is 40 north latitude, and the latitude of Capricorn is 23.5 south latitude, which is a right triangle with an acute angle of 63.5).

A.0.5m B. 1m C. 2m D. 2.5m

5. "When we meet in Gusu, everyone sleeps in the river." People standing on the shore can see the reflection of Gusu people through the calm water. It reflects ().

A. Virtual image formed by light reflection B. Virtual image formed by light refraction

C. Real image formed by light reflection D. Real image formed by light refraction

6. About the spread of sound, the following statement is wrong ()

A. sound travels in one direction along a straight line.

B. When the sound encounters a big obstacle, it will reflect and form an echo.

C. When the sound encounters small obstacles in the propagation process, it can be bypassed.

Sound travels at different speeds in different media.

7. As shown in figure-1, the three rays of light A, B and C converge at point P. If a plane mirror is arbitrarily placed in front of point P, then ().

The three reflected rays may or may not intersect at a point.

B. Three reflected rays cannot intersect at one point.

C. three reflected rays must intersect at one point.

D the extension lines of the three reflected rays intersect at a point behind the mirror.

8. The following statement about light phenomenon is true ()

A. When light diffuses, it does not obey the law of light reflection.

B. When the light obliquely enters the water from the air, the refraction angle is greater than the incident angle.

C after sunlight enters the earth's atmosphere, its propagation path may be curved.

D. The flat mirror can image, and it is an enlarged virtual image.

9. When studying the experiment of convex lens imaging, it is found that when the distance from the object to the convex lens is 5cm, the convex lens becomes an upright image; When the distance from the object to the convex lens is 8cm, it becomes an inverted image. The following statement is true ()

A. When the distance from the object to the convex lens is 3cm, it becomes an enlarged real image.

B. When the distance from the object to the convex lens is 10cm, it becomes an enlarged real image.

C. When the distance from the object to the convex lens is 13cm, it must be an inverted and reduced real image.

D. When the distance from the object to the convex lens is 17cm, it must be an inverted and reduced virtual image.

10. When a bee flies with nectar, its wings vibrate 300 times per second on average, and when it does not carry nectar, it vibrates 440 times per second on average. Experienced beekeepers can tell whether bees fly out to pick flowers or fly home with honey. Beekeepers mainly distinguish other things according to what characteristics ().

A. the tones of sounds are different. B. The loudness of the sound is different

C. Different flight path shapes D. Different flight heights

Second, fill in the blanks

1 1. As shown in the figure, -2 is a parallel beam from two endpoints of the sun to the moon. When observing a solar eclipse, different observers can observe it at points A, B, C, D and E on the earth's surface or at points F, G, H, I and J in the outer space of the earth. In the above 10 region, a total solar eclipse can be observed. It can be observed that the position of annular eclipse is _ _ _ _ _ _ _ _ _ _ _ _; It can be observed that the position of the partial solar eclipse is _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _.

12. When pouring water into a thermos bottle, the sound tone becomes more and more _ _ _ _ _. This sound is produced by the _ _ _ _ _ _ _ vibration in the bottle.

13. Open your eyes, stretch out your right hand, cover your eyes with four fingers together and look at the sun. You will see a piece of red in front of you, indicating that red blood can be transmitted or reflected _ _ _ _ _ _ _ _ _.

14. Solar eclipses usually occur around _ _ _ _ _ _ of the lunar calendar.

15. "The monkey fished for the moon with a sieve." When the monkey fished for the moon, waves were generated on the water. At this time, the moonlight reflected on the water, and the moon in the water disappeared.

16. Among seven kinds of visible light, namely red, orange, yellow, green, blue, indigo and purple, the color light with the shortest wavelength is _ _ _ _ _ _ and the color light with the longest wavelength is _ _ _ _ _ _.

17. The "sight distance" of normal eyes is _ _ _ _ _ cm. Xiaohong wants to carefully observe the skin on her face through the mirror, so the most suitable distance between the small mirror and her eyes should be around _ _ _ _ _ _ _ cm (Xiaohong has normal vision).

18. In the evening, some students fell asleep, and the karaoke bars outside the school were still open, and some students were awakened by singing. A classmate got up and closed the window. Student b simply covered her head with a quilt and fell asleep. C students go to karaoke bars and ask to turn down the volume. The method they adopt to reduce noise is _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _.

19. As shown in Figure -3, standing on a high place like this and calling to the distance, its purpose is _ _ _ _ _ _ _ _.

20. As shown in Figure -4, a person seems to have a fish at point A. If you want to illuminate the fish in the water at point A with the light of a flashlight, the light of the flashlight should be aimed at _ _ _ _ _ _ _ _. (Fill in B, C, E and D first)

Third, experimental inquiry questions.

2 1. zhong -5, can you explain their acoustic principles?

Fourth, drawing questions.

22. As shown in Figure -6, a beam of light AB emitted by point power supply S hits the mirror MN, and CD is the reflection of another incident light emitted by S. Please draw the position of point power supply S in the figure.

23. In Figure -7, MN is the optical axis of the lens and the image of AB. Draw the lens in the appropriate position in the picture and find out the position of the focus.

24. As shown in Figure -8, placing concave lens A in front of convex lens B at 10cm can make a beam of light parallel to the main optical axis pass through two lenses and converge on the screen S of Nie convex lens at 15cm. If the concave lens is removed and the position of the convex lens and the screen remains unchanged, then a point light source C can be placed on the convex lens axis 30cm away from the convex lens, so that the point C can also be imaged on the screen.

Try to make the focal point f of concave lens and find its focal length F.

Fifth, the calculation problem.

25. As shown in Figure -9, a beam of light obliquely downward at an angle of 45 degrees with the ground is blocked by one side of a pair of parallel plane mirrors and reflected to the ground many times. Given that the incident point is h from the ground and the distance between mirrors is a, what is the total optical path after being repeatedly reflected by the mirrors? What is the number of reflections?

In 2006, the new curriculum standard people's education edition last semester eighth grade physics examination paper.

Reference answer

One,

1.C

2.D

3.A

4.C

5.A

6.A

7.C

8.C

9.B

10.A

Second,

1 1.h； c； b、D、G、I

12. High air column

red

14. Grade one

15. Diffuse reflection

16. Purple

17.25; 12.5

18. block noise propagation; Weakening in the human ear; Weaken from the sound source

19. Concentrated sound waves travel far.

20.b (according to the reversibility of light)

Third,

Figure 2 1. A means that the sounding object is vibrating (or the sound is generated by the vibration of the object). Figure B shows that the vibration of the steel ruler can make a sound (or the sound is related to the vibration speed of the object). Figure c shows the reason of echo location.

Figure A -30

The incident light SC of CD passes through AB at S, then S is the position of point light source.

23. as shown in figure A -3 1

(1) connecting MN to O, where O is the center of the convex lens; ② When the incident light parallel to the main optical axis intersects with the convex lens, A crosses to C, and C connects to MN to F, where F is the focus of the convex lens.

Figure A -32

25.① ②

References:

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