Physical light phenomenon problem-solving exercises in the second day of junior high school

1.(20 10. Weifang) The scene of the 60th National Day military parade is shown in the picture. The following statement is correct (D).

A. The military emblem on the flag bearer's hat shines, because the military emblem is the light source.

B the whole queue is uniform, and the audience is judged by the refraction of light.

C. the neat footsteps of the PLA are caused by air vibration.

D. the orderly footsteps of the people's liberation army are transmitted to the audience through the air.

2.(20 10. Weifang) 20 10 Shanghai World Expo is called "Green World Expo" with the theme of "Better City, Better Life" and "Haibao" as the mascot, and attaches great importance to energy conservation and environmental protection. The following statement is true (a)

A. The balloon in the sun is blue, because it only reflects blue light in the sun.

B) Hydrogen is filled in the Haibao balloon, mainly because the density of hydrogen is higher than that of air.

C the mechanical efficiency of the motor in the Expo site is 100%.

D. The motors in the Expo Park work according to the principle of magnetic effect of current.

1 1.(20 10. Linyi) The following statement is correct (c)

A. The reflection of the shore scenery in the water is formed by the refraction of light.

Rainbow is formed by light reflection after rain.

C. In order to diffuse light, the film curtain is made of coarse cloth.

D. The film curtain is made of coarse cloth to make the light mirror-reflect.

12.(20 10. Linyi) Which of the following phenomena is not caused by the straight-line propagation of light (b)

A. shadow B. mirage on expressway C. pinhole imaging D. solar eclipse

3.(20 10. Suqian) Of the four scenarios shown in the figure, (b) belongs to the phenomenon of light reflection.

6.(20 10. Nansha) Of the four scenes shown in the picture, the one that belongs to the straight-line propagation of light is (a).

1 1.(20 10. Shaoxing, Zhejiang) Among the following figures, the description of the phenomenon or conclusion is incorrect (C).

(20 10. Zhanjiang) Among the four scenes shown in the figure, (a) belongs to the linear propagation of light.

(2065438+20l0。 Fuzhou) On the evening of 20l 065438+ 10 15, an annular eclipse spectacle appeared at sunset over Fuzhou. As the picture shows, a golden hook-shaped sun is very spectacular. This phenomenon is caused by (a)

A. straight-line propagation of light B. reflection of light C. refraction of light D. dispersion of light

(20 10. Suzhou) Among the following light phenomena, (c) is formed by the reflection of light.

(20 10. Taizhou) The distance between the examinee and the eye chart is required to be 5m. As shown in Figure 3, the distance between the eye chart and the plane mirror is 3m. In order to meet the measurement requirements, the distance between the person and the plane mirror should be (C).

A. 1m B. 1.5m C.2m D.3m

1.(20 10. Jinhua) The optical principle of hand shadow representation on the right is (D).

A. Reflection of light B. Refraction of light

C. plane mirror imaging D. light travels in a straight line in the same substance

2.(20 10. Wenzhou) In the "Little Scientist" competition, there is an event called "Bouncing against Things" (pictured), which requires participation.

? The competitor shoots the ball on the plane mirror, bounces off the plane mirror and hits the object in the target area. In which direction the player hits the ball in the launching area, the most likely goal is (D).

? A. towards OA. B. towards OB

? C. along the OC direction? D. along the OD direction

3. Many idioms we have learned contain physical knowledge. Which of the following idioms is a "shadow" formed by light reflection (A)

A. a glass of bow and snake shadow B. inseparable C. alone D. immediate effect

6.(20 10. The following are common light phenomena in our daily life, and the correct explanation is (d).

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

B. myopia glasses are convex lenses.

C. Seeing the fish in the water on the shore is the true image of the fish.

D. The red light shines on the actress wearing a white coat and a blue skirt. The audience sees that her coat is red and her skirt is black.

(2.(20 10/0. Nanjing) In the phenomenon shown in the figure, (a) is formed by the reflection of light.

(20 10. Wuhan) is an experimental device to explore the reflection law of light, as shown in the figure. The following operation is incorrect (b).

A. place the cardboard ENF vertically on the plane mirror.

B, a bunch of glossy cardboard hits the O point at a certain angle, and the reflection angle and incident angle are measured with a scale.

Change the direction of incident light and observe how the direction of reflected light changes.

D. Fold the cardboard NOF forward or backward, and observe whether the reflected light can be seen.

1.(20 10. Jining) Among the four phenomena shown below, the straight-line propagation of light is (D).

A. Tower in the water B. Broken branches on the water C. Flowers in the mirror D. Hand shadow

Second, fill in the blanks

15.(20 10. Nansha) Xiao Yang's family bought a brand-new and beautiful car. She was so happy that she observed the inside and outside of the car. Through observation, Xiaoyang found that many parts of the car used physical knowledge. Here are a few items she listed. Please help her finish them.

(1) There are many uneven patterns on the tire to increase the friction between the tire and the ground.

(2) The front windshield is installed obliquely to avoid interference with the driver's sight due to _ _ _ _ plane mirror imaging (or light reflection) _ _ _ _;

(3) The engine is a gasoline engine. From the perspective of renewable energy, gasoline is a non-renewable energy. (You can choose "renewable" or "non-renewable")

(4) She checked the instructions and found that the specification of the headlight bulb is "12V 25W", and the electric energy consumed by this bulb when it works normally 1min is _ _ _1500 _ _ _ j.

(20 10. Fuzhou) If the angle between the incident light and the plane mirror is 40, the reflection angle is _ _ _ 50 _ _; When the incident angle increases 10, the reflection angle increases _ _ 10 _ _.

(20 10. Nantong) An interest group poked a small round hole in the center of the bottom of an empty can, cut off the top, covered it with plastic film, and made a simple pinhole camera. As shown in the figure, place it horizontally and fix a small light bulb with the same height as the left hole. When the light bulb emits light, you can see the inverted filament on the plastic film (choose "inverted" or "upright"), and the size of the image becomes larger (choose "larger", "smaller" or "unchanged"). If only the small round hole is changed into a triangular hole, the image shape will remain unchanged (you can choose "change" or "unchanged").

(20 10. Guangzhou) Xiaoming is standing on the subway platform. Through the glass screen door, he can see the billboard on the vertical wall on the other side of the driveway and his virtual image behind the glass screen door. According to this phenomenon, Xiao Ming designed an experiment to roughly measure the distance d between the glass screen door and the billboard on the other side of the driveway on the platform. The experimental steps are as follows. Please complete the relevant content.

(1) Xiaoming moves back and forth relative to the glass screen door until he observes that his image falls on the billboard;

(2) record your position;

(3) Measure the distance from your workstation to the glass screen door.

In addition to the recording tool, the instrument that Xiao Ming must use to complete the above experiment is a scale. The distance measured in step (3) is the distance d from the glass screen door to the billboard, and the physical basis is that the distance from the image to the mirror is equal to the distance from the object to the mirror.

16.(20 10. Yangzhou) Xiaoming used flat glass, two identical candles and other equipment to explore the characteristics of flat mirror imaging.

(1) The purpose of selecting the glass plate is _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _.

(2) The purpose of choosing two identical candles is _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _

14.(20 10. Yangzhou) The inverted "shadow" of the bridge in the river and the "shadow" of the vertical pole are caused by the _ _ _ _ _ reflection of light, while the latter is caused by the linear propagation of light.

2.(20 10. Luzhou) Gao Kun, a scientist from China, who is known as the "father of optical fiber", won the 2009 Nobel Prize in physics for his research achievement of "optical transmission in optical fiber is used for optical communication". The transmission of light in glass fiber is that every time the light is emitted from the inner glass core to the interface of the outer cladding, it will be reflected without refraction, so that the light will travel far along the inner glass core in constant reflection. As shown on the right, please answer as shown in the figure: When increasing the incident angle of incident light AB, the incident angle of CD light will increase (optional "increase", "decrease" or "unchanged"), and point D will move to the right (optional "left" or "right").

6.(20 10. Wuhu) Place the lighted candles in front of the self-made pinhole imager and adjust their positions to get a clear reflection of the candles, as shown on the screen. Please determine the position of pinhole O on the imager in the figure (leaving drawing traces). If the candle is slightly close to the imager, the image of the candle will become larger (select Bigger, Smaller or No

6. Answer:

15.(20 10. Guilin) As shown in the picture, it is the symbol of our city-Elephant Trunk Hill. Because light travels in a straight line, we can see it far away. Its reflection in the Lijiang River is caused by the reflection of light.

18. (Chengdu, 20 10) As shown in the figure, the bridge is imaged through the calm water surface, and the semicircular bridge hole and its image are combined into a circle. If the bridge length is 45 m, the image length of the bridge is 45 m. If the diameter of the middle circle is l0 m, the distance from the top of the circle to the water surface is 5 m. 。

Third, drawing questions and experimental questions.

18.(20 10. Nansha) As shown in the figure, there is a luminous point S and its two rays in front of the plane mirror. Please image S in the plane mirror in the figure and make the reflected rays of these two rays.

Answer:

25.( 1) (20 10. Wuxi) As shown in Figure A, a beam of light is reflected on a plane mirror. Please draw the reflected light of incident light AO (normal line is required).

Answer:

(20 10. Guangzhou) Draw the incident light reflected by the plane mirror.

Answer:

(20 10. Yantai) Bicycle is a convenient means of transportation, which contains a lot of physical knowledge. For example, bicycle taillights contain optical knowledge. They don't glow by themselves, but at night, when the car lights shine on the taillights, they will be reflected to attract the driver's attention. The structure of the taillight is shown in the figure. Please draw the reflected light in the picture and explain its characteristics.

Answer: As shown in the figure,

The incident light irradiates in parallel with people, and the reflected light irradiates in parallel. Reflected light is opposite to incident light.

(Give points for one answer)

4.(20 10. Henan) As shown in the figure, a plane mirror is placed at the O point, so that the sunlight with an angle of 60 degrees from the horizontal direction will be reflected by the O point and enter the P window horizontally. Please draw the position of the plane mirror in the figure and mark the degree of the reflection angle.

Answer:

5 (20 10. Longyan) Please draw the normal light and reflected light in the picture respectively, and calculate the reflection angle as 30.

33.(20 10. Xiangfan) The light hits the plane mirror at an angle of 30, as shown in the figure. Please draw its reflected light according to the law of light reflection, and indicate the reflection angle.

Answer:

Fourth, the experimental questions

14. (1) (2010. Nansha) The picture shows Xiaogang's flat mirror imaging device. Put a lighted candle in front of a vertical glass plate, and you can see the image of the candle behind the glass plate.

Xiaogang took a candle the same size as the lighted candle and moved it behind the glass plate. When it moves to B, you can see that it completely overlaps with the image. Here, the physical method of _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _

② Xiaogang also found that the image of the candle at point B could not be formed on the light screen. This experiment shows that the image formed by a plane mirror is _ _ _ _ _ _ _ _ (fill in "real" or "imaginary").

(20 10. Jiaxing) Xiao Ming saw a demonstration experiment of the teacher when he was studying the Propagation of Light. The process is as follows:

(1) Shoot the laser pointer into the water, and observe that the light is a straight line (as shown in the figure);

② At point A, slowly inject the hypotonic solution into the water with a funnel, and observe whether the light is bent;

(3) After stirring, it is observed that the light becomes straight again.

Xiao Ming's result based on the above phenomenon is correct (D).

A. the propagation of light needs medium B. Light only travels in a straight line in water.

C. Light cannot travel in a straight line in a hypo solution. D. Light can only travel in a straight line in the same homogeneous medium.

7.(20 10. Longyan) In the experiment of exploring the imaging characteristics of flat mirror:

(1) Put a lighted candle in front of the glass plate, and then move an unlit candle behind the glass plate.

Until it coincides with the image of the candle in front. If you replace the candle behind the glass plate with a light screen, it will be behind the glass plate.

Observing the light screen, you can't observe the image of lighting candles in front of the glass plate (fill in "can" and "can't").

(2) Record the following experimental data.

Object distance /cm image distance /cm [Source: zxxk.com] Image and object size comparison

The first time was 12.0 12.o and so on.

The second time is 15.o 15.0, etc.

Experiments show that the size of the image is equal to the size of the object, and the distance from the image to the plane mirror is equal to the distance from the object to the plane mirror. 5.(20 10 Jingmen) When exploring "the characteristics of plane mirror imaging", we used glass plates instead of plane mirrors to do experiments:

(1) Put a lighted candle in front of the glass plate, then take an unlit candle and move it behind the glass plate until it coincides with the image of the candle in front. If the candle behind the glass plate is removed and a light screen is placed in its place, the image of lighting the candle in front of the glass plate cannot be seen on the light screen.

(2) The experimental results show that the image and the object are the same size; The distance from the image to the plane mirror is equal to the distance from the object to the plane mirror.

8.(20 10. Laiwu) (3 points) In the process of exploring optical experiments:

(1) Xiaoming uses the device shown in the figure to study the reflection law of light, including a foldable light screen, which can not only present light in the experiment, but also play an important role in _ _ _ _ verifying whether the reflected light is on the same plane as the incident light and the normal.

(2) Xiaoming explored the characteristics of flat mirror imaging by using transparent glass plates, two identical candles and other equipment. The purpose of choosing two identical candles is to verify whether the size of the image and the object are equal.

(3) When Xiao Ming is doing the experiment of "Exploring the imaging law of convex lens", the positions of candles, convex lens and light screen are as shown in the figure. After lighting the candle, a clear image was obtained on the screen. Therefore, the following statement is correct _ _ _ c _ _ _

A. What you get is a positive and restored real image.

B, the obtained image is a real image with inverted magnification.

C. Move the candle to the left and adjust the position of the light screen to get a smaller and clearer image.

D. move the candle to the right a little. To get a clear image, please move the screen to the left.

10.(20 10. Longyan) In the experiment of exploring the imaging characteristics of flat mirror:

(1) Put a lighted candle in front of the glass plate, and then move an unlit candle behind the glass plate.

Until it coincides with the image of the candle in front. If you replace the candle behind the glass plate with a light screen, it will be behind the glass plate.

Observing the light screen, you can't observe the image of lighting candles in front of the glass plate (fill in "can" and "can't").

(2) Record the following experimental data.

Object distance /cm image distance /cm [Source: zxxk.com] Image and object size comparison

The first time was 12.0 12.o and so on.

The second time is 15.o 15.0, etc.

Experiments show that the size of the image is equal to the size of the object, and the distance from the image to the plane mirror is equal to the distance from the object to the plane mirror.

28.(20 10. Jixi) When a group of students were exploring the characteristics of flat mirror imaging, they put the lighted candle A on one side of the glass plate and saw the image of a candle behind the glass plate.

(1) At this time, another identical candle B moved back and forth on the paper behind the glass plate, and found that it could not completely coincide with the image of candle A (Figure A). You have analyzed that the reason for this situation may be that the glass plate is not placed vertically.

(2) After solving the above problems, the images of candle B and candle A can completely overlap, indicating that the images and objects are equal in size.

(3) Figure B shows the positions of the corresponding points of the images and objects recorded on the white paper after three experiments. How should they use and process the information in this "white paper" to draw the next experimental conclusion?

_ _ _ _ _ _ _ _ Connect the corresponding points of the image and the object, judge whether the connecting line is perpendicular to the mirror surface, and measure the distances from the two points to the mirror surface respectively.

Leave (or fold the paper in half along the mirror position, and judge whether the two points of the image and the object overlap _ _ _ _ _ _ _.

(4) They found a group of students next to them putting glass plates and candles on grid paper to do experiments. Which do you think is better, white paper or plaid paper? State your reasons: _ _ _ Grid paper can directly judge the positional relationship between the object and the image (it should be easier to judge whether the line between the image and the object is perpendicular to the mirror) _ _ _.