Write a group of questions about lenses and their applications.

1. After sunlight passes through a lens, a point on the back white paper can be illuminated very brightly, indicating that this is a _ _ _ _ _ _ _ _ lens.

2. When showing a movie, in order to get a clear and larger image on the screen, the screen of the movie projector should be _ _ _ _ _ _ _ _ _, and the lens should be moved at the same time.

3. Put a convex lens at the sun, and a bright spot appears on the white paper under the mirror, which is called _ _ _ _ _ _ _. The distance from the optical center of the lens to the bright spot is measured as 5 cm. If used as a camera lens, the distance from the object to the lens should be at least greater than _ _ _ _ _ _ _.

4. Put a lens next to the convex lens, and the sunlight will not converge into a bright spot after passing through it, indicating that this lens is a _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _.

5. The lenses of both the camera and the projector are equivalent to convex lenses, but the camera adopts the imaging law that convex lenses form _ _ _ _ _ _ _ _ _ _ _ _.

6. Put a bottle bottom on the ground and find that the object at the bottom of the bottle has become bigger, which means that the edge of the bottle bottom is _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _

7. The eyeball is like a camera, and the interaction of _ _ _ _ _ _ is equivalent to a convex lens, focusing the light emitted by an object on _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _

8. Myopia of the eye is caused by the fact that the image distance of the object imaged in the eyeball is too _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _.

9. The objective lens and eyepiece of microscope are convex lenses. The sample passes through the objective lens to form a _ _ _ _ _ _ _ _ _ _ _ lens.

10. There is an astronomical telescope. The objective lens and eyepiece are convex lenses, and distant celestial bodies form _ _ _ _ _ _ _ _ _ _ _ _ through the objective lens. The eyepiece is equivalent to a _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _

1 1. has the following optical elements: (a) plane mirror, (b) convex mirror, (c) concave mirror, (d) convex lens and (e) concave lens. Which of the following optical instruments or appliances is used? Please fill in the blanks with the corresponding letters. _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _

12. The calibration part of a common thermometer is a triangular body with a cross section as shown in Figure 3-44, and its front is an arc, so that the extremely fine mercury column in the thermometer can be clearly seen, which is convenient for reading. This is because circular glass is equivalent to _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _

Figure 3-44

13. In the lens imaging experiment, the image of candle flame is at the lower edge of the screen. If you don't change the position of the candle flame and the screen, but plan to move the lens to move the image to the center of the screen, you should move the lens to _ _ _ _ _ _ _.

14. The lens of myopia glasses is _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _

Second, multiple choice questions

1. Among the following optical instruments, the one that diverges light is

A. convex lens

B. periscope

C. plane mirror

D. concave lens

2. To make a beam of parallel light remain parallel after passing through two identical convex lenses, the main optical axes of the two convex lenses should coincide, and the distance between the two lenses is

A. equal to a focal length

B. equal to twice the focal length

C. More than twice the focal length

D can be equal to any value.

3. Regarding the understanding of virtual image, the following statement is correct.

A. a virtual image is not an image.

B. the virtual image cannot be reflected on the light screen.

C. a virtual image is an enlarged image.

D. a virtual image is an unclear image.

4. As shown in Figure 3-45, one end of paper tube A is covered with a layer of translucent paper, and one end of paper tube B is embedded with a convex lens. Two paper tubes are sleeved together to form a model camera. In order to get a clear image at the A end, the distance between A and B should be adjusted. At this time,

Figure 3-45

A. Look into the barrel with your eyes toward the B end to see if the image is clear.

B. If you can see the nearby scenery clearly, you should pull B outward to increase the distance between A and B when you see the shadow in the distance.

C-end A should face the bright outdoor, and pipe B should face the dark indoor, otherwise it can't be seen clearly.

D.B end should face the bright outdoor and A end should face the dark indoor, otherwise it is not clear.

When taking pictures with a camera with a certain focal length, you can take the following measures if you want to reduce the image of people.

A. Keep the camera away from the crowd

B keep the camera away from people and adjust the distance between the lens and the negative closer.

C. Keep the camera close to people

D Keep the camera closer to the person and adjust the distance between the lens and the negative.

6. For a convex lens with a focal length of 5 cm, the following statement is correct when the light source gradually moves from 8 cm to 20 cm away from the lens.

A. the image and the image distance are getting smaller and smaller.

B. the image and the image distance are getting bigger and bigger.

C. the image becomes smaller and the image distance becomes larger.

D. the image becomes larger and the image distance becomes smaller.

7. A classmate studied the imaging experiment of convex lens and wrote the following four sentences. What do you think is right?

A. the real image is always upside down, and the virtual image is always upright.

B. Both the real image and the virtual image can be enlarged or reduced.

C when the real image is formed, the closer the object is to the convex lens, the bigger the image is.

D. When a virtual image is formed, the closer the object is to the convex lens, the larger the image is.

8. If the lens of a camera is used as the lens of the lens imaging experiment, it is impossible for the following phenomena to occur.

A. see the inverted and reduced image of the object.

B. see the inverted and enlarged image of the object.

C. view the upright and enlarged image of the object.

D. view the upright and reduced images of the object.

9. Xiaoming did the experiment of "studying convex lens imaging" on the optical bench. When the relative positions of the screen, lens and candle flame are shown in Figure 3-46, he can only see clear images on the screen. Judging from this, the focal length of the convex lens he used.

Figure 3-46

A.it must be more than 20 cm.

B. it must be less than 8 cm.

C it must be between10cm and16cm.

D it must be between 8 cm and 10 cm.

10. Xiaoming holds a magnifying glass with a relatively large diameter and stretches out his arms to look at distant objects. He can see images of objects. The following statement is correct.

A. the light entering the eyes must be emitted by the image.

B. the image must be a virtual image.

C.the elephant must be upside down

D. the image must be enlarged

1 1. When listening to the lecture, Xiaoguang wants to shoot the color slide images projected by the projector on the screen with a camera. Because the venue was dark, he used a flash. The photos taken like this.

I didn't see the image projected on the screen clearly, but took some stains on the screen.

B.bright colors are much clearer than no flash.

C. the color is "flashing", only black words and lines are photographed.

D, the effect is the same as when the flash is not used, because the image on the screen is taken, not the actual scene.

12. There is a small mirror under the lens barrel of the biological microscope to increase the intensity of light entering the lens barrel. If you can choose the mirror surface of a small mirror, the best effect is to use it in biology class.

A. concave mirror noodles

B. convex mirror surface

C. plane mirror

D. milky white mirror

13. When using a microscope, the distance of the observed object from the objective lens

A. greater than focal length

B. Less than focal length

C is less than 2 times the focal length and more than 1 times the focal length.

D. More than twice the focal length

14. When using a microscope

A. the objective lens becomes a real image and the eyepiece becomes a virtual image.

B. the objective lens becomes a virtual image and the eyepiece becomes a real image.

C. without the light screen, everything becomes a virtual image.

The real image or the virtual image should be determined according to the object distance.

15. When using a telescope

A. the objective lens becomes a real image and the eyepiece becomes a virtual image.

B. the objective lens becomes a virtual image, and the eyepiece becomes a virtual image.

C because there is no light screen, the objective lens and eyepiece are virtual images.

D. Because the object distance is much larger than the focal length, both the objective lens and the eyepiece are real images.

Experiment and design

1. The following is the process of Xiaohong and Xiaohua exploring the imaging law of convex lens:

(1) Before exploring, Xiaohong pointed three convex lenses at the sunlight, and adjusted the distance between the convex lens and the light curtain to make the sunlight converge a little. The distances from the convex lens to the screen are 48 cm, 15 cm and 4 cm respectively. Xiaohong chose 15 cm convex lens for the experiment, while the other two convex lenses were not used in this experiment.

Tell your opinion: _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _

(2) Both convex lens and light screen are supported. The height of the convex lens center from the desktop is about 6 cm, and the height of the light screen center from the desktop is about 7 cm. There is also a candlestick for holding candles. Xiaohong cut a newly bought long candle into two parts and only inserted one of them on the candle table. Do you think this is necessary?

State your reasons: _ _ _ _ _ _ _ _ _ _ _ _ _ _.

(3) In order to make the light screen accept the image of the candle, in what order should the candle, the light screen and the convex lens be placed on the table for the experiment? __________.

(4) When Xiaohong started her experiment, she put the candle as far away from the convex lens as possible. At this time, where should the light curtain be placed to receive the real image of the candle? It should be placed in _ _ _ _ _ _ _ _ _ _. After getting the real image, put the candle near the convex lens. In which direction should the screen move to receive the real image again? It should move in the direction of _ _ _ _ _ _.

(5) When the candle flame moves to a distance of only 12 cm from the convex lens, the light screen is placed on the other side of the convex lens (for the candle), and no matter how it moves, no real image can be received. Put the screen on the same side of the candle, is it possible to receive the image of the candle?

__________________.

(6) If the image of a candle is observed with eyes, how are the positions of eyes, candles and convex lenses arranged?

__________________.

2. Sometimes the brightness of parallel beams is changed by changing their width (thickness). Is there any way to change the width of parallel beams? Please draw a chart.

(1) makes the beam wider (thicker).

(2) Narrow (thin) the light beam.

Scientific inquiry

The astronomical telescope in the textbook was invented by astronomer Kepler, so it is called Kepler telescope. The objective lens and eyepiece of this telescope are convex lenses, which observe the inverted image of celestial bodies and are not suitable for ground observation. Galileo, a great physicist, also designed telescopes. The objective lens is a convex lens and the eyepiece is a concave lens. People call this kind of telescope galileo telescope. The biggest advantage of this telescope is that it can observe the upright image of distant objects. Please find some convex lenses and concave lenses with different focal lengths, and refer to the method in the textbook Figure 3.5-6 to explore the method of making galileo telescope. Please consult the teacher or consult the information for details.

Summary after chapter

☆ Take a test. How are you doing?

Knowledge and skills

1. 1. convex 2. Stay away from negativity.

3. The focal point of the convex lens is 10 cm.

4. Concave surface

5. Reduce the real image and enlarge the real image

6. Thin

7. Lens, cornea and retina

8. Small, divergent, large, supraretinal, convergent, small

9. Enlarge the solid, the focal length of the adjacent side is in, and the magnification is m 1m2.

10. Zoom out, zoom in, view angle

1 1.a，c，d，b，e，c

12. Convex lens, virtual

13. Up 14. Concave, short

Ii.1.d2.b3.b4.d5.b6.a7.ac8.d9.d11.a12.a1.

Experiment and design

1.( 1) The focal length of the convex lens is too large or too small, which is inconvenient.

(2) It is necessary to do this, because the newly bought candles are longer, so that the centers of the candle flame, convex lens and light screen can be in a straight line.

(3) From left to right are candles, convex lenses and light screens.

(4) 1 multiple focal length to 2 focal length; Stay away from convex lens

5. impossible

(6) The eyes are on the other side of the convex lens relative to the candle.

2. The principle of the method of (1) is shown as 15, 16, 17, where f 1 < F2.

Figure 15 Figure 16

Figure 17

(2) Figures 18,19,20 can be obtained from the reversibility of the optical path.

Scientific inquiry

Galileo telescope's objective lens has a larger focal length and the eyepiece has a smaller focal length. The method is shown in Figure 2 1, and the principle is simple.

Figure 2 1

Fill in the blanks (2 points for each question, 30 points in total)

1. If you want to use a convex lens to turn the light emitted by a small light bulb into parallel light, you should put the small light bulb on the convex lens.

2. The three special rays about the convex lens are: the direction of light propagation through the optical center _ _ _ _; _ _ _ The focus of light parallel to the main optical axis after refraction by the lens; The light passes through the main optical axis of the focus after being refracted by the lens.

3. When the distance from the object to the convex lens is more than 2 times the focal length, it becomes _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _.

4. In the convex lens imaging experiment, when the candle is 36 cm away from the convex lens, it will be imaged as _ _ _ _ _ and _ _ _ _ on the other side screen 20 cm away from the convex lens, and the focal length of the convex lens used is _ _ (fill in "greater than", "equal to" or "less than") 65438+.

5. The lens of the camera is equivalent to a _ _ _ _ _ mirror, and the subject should get the shooting effect of _ _ _ _ _ _ _ _ _ _.

6. The camera uses the aperture to control the amount of light in _ _ _ _. If someone shoots a bright object and then shoots a dark object, the aperture should be appropriate _ _ _ (fill in "up" or "down").

7. In the experiment of reducing the real image of convex lens, the main equipment needed is a scale, a candle, a convex lens and _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _

8. When the object is out of twice the focal length of the convex lens and moves towards the lens (no more than twice the focal length), the distance between the image and the lens will be _ _ _ _, the size of the image will be _ _ _ _ _, and the image obtained will be _ _ _ _.

9. When the object is placed 40 cm away from the lens on the main optical axis of the convex lens, and the focal length of the lens is 15 cm, the image formed by the object through the lens is _ _ _ _ _ _ _ _ _. If the object moves 15 cm in the direction of the lens, the image of the object will move in the direction of _ _ _ _ _ _, and at the same time the image will become _ _.

10. The slides of the slide projector should be _ _ _ inserted behind the _ _ _ lens, slightly farther than the focus. At this time, the image on the screen is _ _ _ _ _ _ _ _.

1 1. The lens of slide projectors and movie projectors is a _ _ _ _ mirror, and the object should be placed in _ _ _ _ _, such as _ _ _ _ _. If the screen is large, the slide projector and movie projector should keep a distance of _ _ _ from the screen.

12. There are _ _ _ _ convex lenses in the microscope, and the one near the eyes is called _ _ _ _ _, and its function is _ _ _ _ _. If you want to see the stars in space clearly, you need to use _ _ _ _ _, which has _ _ _ convex lenses. The one near the eyes is called _ _ _ _, and the one near the object.

13. The light reflected by external objects passes through _ _ _ _, _ _ _, enters the eyeball from _ _, and then refracts through _ _, vitreous body to form a clear object image on _ _ _.

14. If the _ _ _ _ of the eyeball and the _ _ _ of the lens and the light reflected by distant objects are refracted by _ _ _ _, the image of the object will fall on the _ _ _ _ of the retina, causing myopia.

15. When a cat walks from a dark place to the sun, _ _ _ _ will become _ _ _ _, which is used to reduce the stimulation of the sun on the eyeball and is controlled by the smooth muscle in _ _ _ _.

Second, multiple-choice questions (4 points for each question, a total of 44 points)

16. When the distance between the object and the convex lens is 30 cm, an enlarged real image is obtained on the light screen. If the object is moved to a distance of 45 cm from the convex lens along the principal axis, the imaging situation must be ().

A. Enlarge the real image B. Equal the real image C. Reduce the real image D. Three situations are possible.

17. The object moves from a distance of 12 cm to a distance of 20 cm from the convex lens. By adjusting the position of the light screen, an inverted enlarged image can always be obtained on the light screen, indicating that the focal length of the convex lens may be ().

A. 10/0cm B.20 20cm C.12cm D. None of the above are correct.

18. When doing the convex lens imaging experiment, the candle is 0/5 cm away from the convex lens and becomes an enlarged image on the light screen. The following statement is incorrect ().

A. When the candle is 40 cm away from the lens, it must be a reduced real image. B. When the candle is at a distance of 18 cm from the lens, it may be an enlarged real image. C. When the candle is 20 cm away from the lens, it must be an enlarged real image. D. When the candle is 6 cm away from the lens, it must be an enlarged virtual image.

19. The distance between the lens of the slide projector and the slide can be adjusted between 10 cm~20 cm and 20 cm. Now because the original lens is damaged, which of the following components should be selected as the lens ()?

A. A convex lens with a focal length of 5 cm B. A concave lens with a focal length of 10 cm

C. Convex lens with focal length of 10 cm D. Convex lens with focal length of 20 cm

20. Take pictures of your family with a camera. The distance between the person and the camera lens and the distance between the negative and the camera lens are () respectively.

A. greater than 2f, less than f B, greater than 2f, less than 2f and greater than F.

C less than 2f, greater than f, greater than 2f D, greater than f and greater than 2f.

2 1. Surveying and mapping, surveyors often need to take aerial photography of the ground on the plane, which is called aerial photography. If the focal length of the lens of an aerial camera is 50 mm, the distance between the negative and the lens is ().

A. 100 mm, B.50 mm, c.slightly more than 50 mm, D.50 mm.

22. When showing a slide show, the screen shows the image on the slide show ().

A. virtual image with upright magnification B. real image with upright magnification C. virtual image with inverted magnification D. real image with inverted magnification

23. When imaging with a convex lens, the following statement is correct ().

A. the real image is always positive, and the virtual image is always inverted. Both the real image and the virtual image can be enlarged or reduced.

C. When forming a real image, the closer the object is to the convex lens, the bigger the image is. D. When a virtual image is formed, the closer the object is to the convex lens, the larger the image is.

24. When an object is placed in front of the convex lens, a clear enlarged image of the object is obtained on the screen 20 cm away from the other lens. If the object is moved to 20 cm in front of the lens, in order to still get a clear image on the screen on the other side of the lens, the moving direction of the screen and the imaging size are ().

A. the light screen is close to the lens to form a reduced image b, and the light screen is close to the lens to form an enlarged image.

C, the light screen is far away from the lens to form an enlarged image D, and the light screen is far away from the lens to form a reduced image.

25. There is a candle in front of the convex lens. By adjusting the position of the lens and the light screen, an enlarged and clear image can be presented on the light screen; If the position of the convex lens remains fixed and the position of the candle and the light curtain is reversed, then ()

A. images are no longer displayed on the optical screen. B. presenting images of the same size on the optical screen.

C. presenting a reduced image on the optical screen D. presenting an enlarged image on the optical screen.

26. No matter far or near, for normal people, it can make objects fall on the retina, mainly because of ().

A. the retina can move back and forth to adjust B. the diameter of the eyeball can be adjusted at will.

C. the pupil can be narrowed or enlarged. The curvature of the lens can be adjusted.

Three. Experimental questions (3 points for each question, 9 points in total)

27. In the experiment of exploring convex lens imaging, the convex lens, candle and light screen must be placed on _ _ _ _, and between the other two devices, so that the centers of the candle flame, convex lens and light screen are roughly on _ _ _ _ _.

28. When a clear and restored real image is obtained on the light screen, it means that the candle is on the convex lens _ _ _ _ _; If you want to get a clear and enlarged real image, the candle should move in the direction of _ _ _ _ _, and the screen should also move in the direction of _ _ _ _ _. The size of the image is gradually _ _ _ _. If no matter how you move, the screen can't receive the image of the candle, indicating that the candle is within the range of _ _ _ _.

29. In the experiment of exploring the imaging law of convex lens, if the light screen can't receive the image no matter how it moves, the reasons may be: (1) _ _ _; (2)_____ ; (3)_____.

30. When exploring the imaging law of convex lens, a classmate first shines parallel light on the convex lens and gets a minimum bright spot on the screen 20 cm away from the convex lens. The student measured the data shown in the table below with this lens. Please fill in the form and answer:

Object distance (cm) The image distance (cm) of the object range is the inverted image size of the image range.

60 30

50 33.3

40 40

30 60

2 100

20

15 -60

(1) What is the focal length of this convex lens?

(2) What is the dividing point between the enlargement and reduction of real images?

(3) What is the dividing point between the real image and the virtual image?

(4) What is the position of the image when the object magnifies the reality?

(5) When the object is restored to reality, what is the position of the image?

(6) Can you measure the image distance of the virtual image? Tell me your method.

Four, drawing questions (17 points)

3 1.(6 marks) Fill the box of the drawing with appropriate optical elements.

32.(6 points) Complete the light path diagram below.

33.(5 points) Please fill in the blanks with lenses and mirrors.

[Reference answer]

1. Focus; 2. Don't change, converge and be parallel; 3. Inverted, restored, true, camera; 4. Inverted, reduced, solid, less than; 5. Convex lens, more than 2 times beyond the focal length, light screen, inverted, reduced and stereoscopic; 6. Enter the camera and turn on the camera; 7. Light screen, convex lens, candle flame and light screen center; 8. Become bigger, bigger and more solid; 9. Inverted, reduced, stereoscopic, away from the lens, inverted, enlarged, stereoscopic;

10. Inverted, raised, inverted, enlarged and solid; 1 1. Protrusion, between the focal length and twice the focal length, more than twice the focal length, inverted to enlarge the real image and distance; 12. Second, the eyepiece is equivalent to a magnifying glass, objective lens and telescope. Second, the eyepiece, objective lens, inverted, reduced and stereoscopic;

13. Cornea, aqueous humor, pupil, lens and retina; 14. The anterior-posterior diameter is too long, the curvature is too large, and the lens is in front; 15. Pupils, pupils and sclera

16.D 17。 D 18。 C 19。 C 20。 B 2 1。 C 22。 D 23。 C 24。 A handful of 25. C 26。 D

27. optical bench (Taiwan), convex lens, same height; 28.2 times the focal length, close to the lens, far from the lens, larger, 1 times the focal length; 29.( 1) The candle flame center, convex lens and light screen are not at the same height. (2) The candle is in focus. (3) The candle is within 1 multiple focal length.

30.( 1) concave lens (2) convex lens (3) concave lens (4) convex lens (5) convex lens (6) flat mirror 3 1.32.