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An interesting story about a physicist in 500 words

⑴ Physics in my heart essay for the second grade of 500 words

Physics is a natural subject with a long history. With the development of science and technology and the progress of society, physics has penetrated into human life. various fields. For example, just looking for knowledge about optics in cars has the following points:

1. The rearview mirror outside the car cab is a convex mirror

Using the divergent effect of the convex mirror on light and the characteristics of upright, reduced, and virtual images, the actual object seen is small and the observation range is larger. Ensure driving safety.

2. The reflector in the car headlight is a concave mirror

It is made by utilizing the property of a concave mirror to reflect the light emitted by the light source placed at its focus into parallel light.

3. Car headlights are always equipped with a glass shade with horizontal and vertical stripes

Car headlights are composed of a bulb, a reflector and a glass cover in front of the lamp. According to the knowledge of lenses and prisms, the car headlight glass cover is equivalent to a combination of lenses and prisms. When driving at night, drivers must not only see clearly the road conditions ahead, but also clearly see people on the roadside, road signs, forks, etc. Lenses and prisms refract light, so the lampshade disperses the light in the required direction according to actual needs through refraction, so that the light can evenly and softly illuminate the road ahead of the car and the scenery on the roadside. At the same time, this astigmatism lampshade can also Make part of the light slightly refracted upward to illuminate road signs and milestones, thereby ensuring driving safety.

4. After the car is equipped with tinted glass, it is difficult for pedestrians to see the faces of the people in the car.

The tinted glass can reflect part of the light and absorb part of the light, so the light penetrating into the car is weak. To see a passenger's face clearly, strong enough light must be reflected from the face and transmitted outside the glass. Because the light inside the car is weak and not enough light is transmitted through, it is difficult to see the faces of the passengers clearly.

⑵ Write an experimental discussion on a physical phenomenon in life (500 words) A short physics paper

The bamboo basket is not empty

— - An example of the tension of water molecules

As the saying goes, "Fetching water from a bamboo basket is empty." In fact, if you are careful, you will find that the water from the bamboo basket is not empty: in the gaps at the bottom and around the bamboo basket, there are Filled with countless water films. What is the reason for this? We have to start with the forces between molecules.

We know that all matter is composed of molecules. The molecules that make up matter are not only constantly moving irregularly, but also have both gravity and gravity that interact with each other. Repulsive force of interaction. Under normal circumstances, the attraction between molecules is equal to the repulsion. If the distance d between molecules at this time is assumed to be the equilibrium distance, then when the distance between molecules is slightly larger than the equilibrium distance, the force between molecules appears as attraction (if it is greater than the diameter of the molecule 10 times, there is almost no force between molecules); when the distance between molecules is less than the equilibrium distance, the force between molecules appears as a repulsive force. When the bamboo basket is immersed in water, due to the gravitational effect of the bamboo strip molecules on the water molecules, the distance between the water molecules in the gaps between the bamboo strips becomes larger when the bamboo basket is lifted, and the force between the molecules is expressed as gravity, forming countless water films. .

In fact, there is a layer of water film on any water surface. This is because some of the faster-moving molecules on the water surface continue to run into the air (i.e., water evaporates), making the distance between water molecules larger, and the attraction between molecules is significantly greater than the repulsive force, thus forming the so-called tension, making the water surface It seems to have a thin and elastic "skin". This is one of the reasons why many small and light insects can walk freely on water. The surface tension here is really not small, enough to make some lightweight plastic rice baskets float on the water without sinking.

But if part of the water film is damaged, other parts will move under the action of gravity. For example, a small boat is made from a cut and cored wooden pencil, wax oil is inserted into the small hole drilled in the back of the boat, and the boat is placed on the water, and the boat moves forward. This is because the wax oil in contact with the water destroys the tension of the water surface, causing the tension of this part of the water surface to suddenly decrease, so the boat moves in the direction of greater tension. In addition, due to diffusion, the wax oil molecules are ejected at a certain speed. Toward the water, because the forces are mutual, a force is also produced to push the ship forward.

You see, the world is so wonderful, even if you draw water from a bamboo basket, it is not empty. Really pay attention to physics everywhere. Let us appreciate this wonderful world from a scientific perspective!

⑶ Qian Xuesen’s story (about 500 words)

Born on December 11, 2011, from Hangzhou, Zhejiang, joined the Communist Party of China in August 1959 , Ph.D.

From 1929 to 1934, he studied in the Mechanical Engineering Department of Shanghai Jiao Tong University. After graduation, he applied for Tsinghua University to study in the United States as a public student. After admission, he interned at Hangzhou Jianqiao Airport. From 1935 to 1939, he studied in the Department of Aeronautical Engineering at the Massachusetts Institute of Technology in the United States and received a master's degree. From 1936 to 1939, he studied in the Department of Aeronautics and Mathematics at the California Institute of Technology in the United States and received a doctorate. From 1939 to 1943, he served as a researcher in the Department of Aeronautics, California Institute of Technology.

From 1943 to 1945, he served as an assistant professor in the Department of Aeronautics, California Institute of Technology (during this period: from 1940 to 1945, he was a communications researcher at the Sichuan Chengdu Aviation Research Institute). From 1945 to 1946, he was an associate professor in the Department of Aeronautics, California Institute of Technology. From 1946 to 1949, he served as associate professor and professor of aerodynamics in the Department of Aeronautics and Astronautics at the Massachusetts Institute of Technology. From 1949 to 1955, he served as director and professor of the Jet Propulsion Center at the California Institute of Technology.

Returned to China in 1955. From 1955 to 1964, he served as director and researcher of the Institute of Mechanics, Chinese Academy of Sciences, and director of the Fifth Research Institute of the Ministry of National Defense. From 1965 to 1970, he served as deputy minister of the Seventh Ministry of Machinery Industry. From 1970 to 1982, he served as deputy director of the Science and Technology Committee of the Commission of Science, Technology and Industry for National Defense and vice chairman of the China Association for Science and Technology. He has also served as the first and second chairman of the Chinese Society of Automation, honorary president of the Chinese Astronautical Society, the Chinese Society of Mechanics, and the Chinese System Engineering Society, executive director of the Presidium of the Chinese Academy of Sciences, and member of the Department of Mathematical Physics. From 1986 to May 1991, he served as Chairman of the Third National Committee of the China Association for Science and Technology. In May 1991, he was elected as the Honorary Chairman of the China Association for Science and Technology at the Fourth National Congress of the China Association for Science and Technology. In April 1992, he was appointed as the honorary chairman of the Presidium of the Chinese Academy of Sciences. In June 1994, he was elected as an academician of the Chinese Academy of Engineering.

He was an alternate member of the 9th to 12th CPC Central Committee and vice chairman of the 6th, 7th and 8th CPPCC National Committee.

He is a pioneer and outstanding representative of China's aerospace science and technology industry, and is known as the "Father of China's Aerospace" and the "King of Rockets". While studying and researching in the United States, he collaborated with others to complete the "Review and Preliminary Analysis of Long-Range Rockets", which laid the theoretical foundation for surface-to-surface missiles and sounding rockets. The hypersonic flow theory he co-proposed with others laid the foundation for the development of aerodynamics. laid the foundation. At the beginning of 1956, the "Opinions on Establishing my country's National Defense Aviation Industry" was submitted to the Central Committee of the Communist Party of China and the State Council. In the same year, based on his suggestions, the State Council and the Central Military Commission established the Aviation Industry Commission, a leading organization for missile and aviation scientific research, and was appointed as a member. In 1956, he was appointed to establish China's first rocket and missile research institute, the Fifth Research Institute of the Ministry of National Defense, and served as the first director. He presided over the completion of the "Establishment of Jet and Rocket Technology" plan, participated in the development of short-range missiles, medium- and short-range missiles and China's first artificial earth satellite, and directly led the "two-bomb combination" of using medium- and short-range missiles to carry atomic bombs. test, participated in the formulation of China’s short-range missile-carrying atomic bomb “two-bomb combination” test, participated in the formulation of China’s first interstellar aviation development plan, and developed and established engineering cybernetics and systems science. He has made pioneering contributions in the fields of aerodynamics, aerospace engineering, jet propulsion, engineering cybernetics, physical mechanics and other technical sciences. He is the founder and advocate of theoretical and applied research on modern mechanics and systems engineering in China.

In 1957, he won the first prize of the Natural Science Award of the Chinese Academy of Sciences. In 1979, he won the Distinguished Alumni Award from the California Institute of Technology. Won the National Science and Technology Progress Special Award in 1985. In 1989, he won the "Little Rockwell Medal", the "World-class Science and Technology and Engineering Celebrity" award and the title of honorary member of the International Institute of Technology. In October 1991, he was awarded the honorary title of “National Outstanding Contribution Scientist” and the First-Class Hero Model Medal by the State Council and the Central Military Commission. In January 1995, he won the "1994 Ho Leung Ho Lee Foundation Excellence Award". In 1999, the Central Committee of the Communist Party of China, the State Council, and the Central Military Commission decided to award him the "Two Bombs and One Satellite Meritorious Service Medal." In October 2006, he won the "Highest Honor Award for the 50 Years of China's Aerospace Industry".

⑷ The sophomore physics paper is about 500 words

Physics is a subject based on observation and experiment. In teaching, consciously guiding students to connect with real life and analyze physical phenomena; using objects around them and conducting physical experiments can stimulate students' interest in learning and deepen their understanding. Here we introduce a set of physical phenomena and experiments related to eggs.

1. Liquid evaporates and absorbs heat

Experiment: Take the newly cooked eggs out of the pot and hold them directly with your hands. Although they are hot, they are still bearable. After a while, when the water film on the eggshell dries, it feels hotter than when it was first picked up.

Analysis: Because there is a layer of water film attached to the newly fished eggshell, at first, the water film evaporates and absorbs heat, causing the temperature of the eggshell to drop, so it does not feel very hot. After a period of time, the water film evaporates. The heat transferred from the inside of the egg causes the temperature of the eggshell to rise again, making it feel even hotter.

2. The nature of thermal expansion and contraction

Experiment: Immediately immerse the cooked eggs in cold water, wait until they are completely cooled, and then pick them up and peel them off.

Analysis: First of all, when the egg is just immersed in cold water, the eggshell shrinks directly when exposed to cold, while the temperature of the albumen does not drop much and the shrinkage is also small. At this time, the main manifestation is that the eggshell is shrinking. Secondly, due to the differences in the thermal expansion and contraction properties of different materials, when the entire egg is completely cooled, the shrinkage rate of the loosely organized albumen is greater than that of the eggshell, and the degree of shrinkage is more obvious, causing the albumen and eggshells to separate from each other, making it more difficult to peel the eggshell. Convenient.

3. Verify the existence of atmospheric pressure

Experiment: Choose a bottle with a diameter slightly smaller than that of an egg, and heat a layer of sand on the bottom of the bottle.

First, light a ball of alcohol cotton and put it into the bottle, then put the small end of a shelled egg downward to block the mouth of the bottle. After the flame went out, the egg was slowly "swallowed" into the belly of the bottle.

Analysis: The burning of alcohol cotton causes the gas in the bottle to heat and expand, and part of the gas is discharged. When the egg blocks the mouth of the bottle and the flame is extinguished, the pressure of the gas inside the bottle becomes smaller due to the temperature drop, which is lower than the atmospheric pressure outside the bottle. Under the action of atmospheric pressure, the elastic eggs are pressed into the bottle.

4. Floating and sinking phenomenon

Experiment: Immerse a shelled egg in a large-diameter glass filled with water. After letting go of my hand, I found that the egg slowly sank to the bottom of the cup. Remove the eggs and add salt to the water to make a salt solution with a higher concentration. Then immerse the egg in the salt solution. After letting go, the egg slowly floats up.

Analysis: The floating and sinking of an object depends on the relationship between gravity and buoyancy. The volume of an object immersed in a liquid is the volume of the liquid it displaces. According to Archimedes' principle, it can be seen that the relationship between the density of an object and the density of a liquid can correspond to the relationship between gravity and buoyancy. Because the density of an egg is slightly higher than that of water, when the egg is immersed in water, the force of gravity is greater than the buoyancy force, so the egg will sink. When immersed in salt water, because the density of salt water is greater than that of the egg, the gravity exerted by it is less than the buoyancy force, so the egg will float.

5. Inertia and frictional resistance phenomena

Experiment: Choose a raw egg and a cooked egg with similar shapes and place them on a horizontal table. Use the same force to rotate them in place. The eggs that can spin quickly are cooked eggs, and the eggs that spin slowly and stop after a few turns are raw eggs.

Analysis: There is liquid egg white inside the shell of a raw egg. When an external force acts on the egg shell to rotate, the egg white continues to remain stationary due to inertia, and there is friction resistance between it and the egg shell, causing the entire egg to rotate. The egg can only rotate slowly. The egg white inside the cooked egg has solidified into protein, and when rotated by external force, the whole egg can rotate quickly.

6. Stable balance of objects

Experiment: Use a raw egg, make a hole at the small end and remove the egg white and yolk in the shell. Slide a heavy object along the hole. Using the big end of the eggshell as the bottom, hold the eggshell in place. Light a candle, drop in candle wax, and seal the weight in the bottom of the eggshell. The candle wax can be sealed to approximately one-quarter of the height of the eggshell. After the prepared eggshell is pushed down, the eggshell can stand up automatically. Make a "tumbler".

Analysis: The weights and candle oil sealed at the bottom of the empty eggshell move the center of gravity of the entire egg body closer to the bottom of the eggshell. The lower the center of gravity, the better the stability. When the eggshell tilts and deviates from the equilibrium position, the center of gravity of the egg body rises. Because the bottom of the eggshell is spherical, the egg body returns to its original equilibrium position under the action of the egg's own gravity.

7. Molecular motion phenomenon

Experiment: An egg with an intact shell can be made into a salted egg by burying it in salt and marinating it for a period of time. Although the shell was still intact, even the yolk inside was salty.

Analysis: Because there are gaps between the molecules of the substance, and the molecules are constantly moving irregularly, the salt molecules diffuse into the egg yolk, making the egg yolk salty.

A set of physical phenomena and experiments related to eggs were collected from the Educational Resources Network

⑸ A 500-word paper on basic physics knowledge

Physics in Earthquakes

Earthquakes were called "earth ox turning over" in ancient times. "Earth ox is a fierce beast in ancient times. It is born with the power of the five elements of heaven and earth. When it moves, mountains and rivers turn upside down, and the universe reverses itself." ". People at the time believed that this monster called the "earth cow" caused earthquakes by rolling over. Now, people already know that the cause of earthquakes is the movement of plates within the earth's crust. There are many physical phenomena that occur along with earthquakes, and you must be interested in learning about some of them.

1. Transverse waves and longitudinal waves

When an earthquake strikes, people will first feel shaking back and forth, and then change to up and down after a while. This is because earthquakes produce both transverse and longitudinal waves, but longitudinal waves propagate faster. Transverse waves refer to waves whose vibration direction is perpendicular to the direction of propagation; longitudinal waves refer to waves whose vibration direction and propagation direction are in a straight line. If both transverse and longitudinal waves propagate along the surface, longitudinal waves vibrate back and forth, and transverse waves vibrate up and down. Using this feature, people can quickly determine the location of the earthquake.

For example: During an earthquake, residents in a certain place first felt the left and right shaking, and then started to shake up and down after 10 seconds. It is known that the longitudinal wave propagation speed is 5 kilometers/second, and the transverse wave is 3 kilometers/second. , how far is the earthquake source from this place?

Assume: The ground is S kilometers away from the earthquake source

The solution is S = 18.75 kilometers

2. ***Vibration

The earthquake is coming At the same time, some buildings in the same place vibrate with a larger amplitude, while others have a smaller amplitude. This is a phenomenon in physics called vibration. Every object has its own frequency, which is determined by its length, shape, material, etc. Buildings also have their own natural frequencies. When an earthquake strikes, if a building's natural frequency happens to be close to the frequency of the seismic wave, then it will vibrate most violently.

Example: Assume that the natural frequency of a steel-concrete structure building is proportional to the square of its height, and the proportional coefficient is 0.5. The frequency of a certain seismic wave is 50 Hz. In this earthquake, what kind of Do high-height steel-concrete buildings vibrate the most?

Assume the height of the building is h, and its natural frequency is f

The relationship between the two is: f = 0.5h2

50 = 0.5h2

Solution: h = 10 meters

3. Physical explanation of abnormal natural phenomena before earthquakes

The occurrence of each earthquake requires a long time of gestation. Only When the underground faults are twisted, rubbed, and ready to explode to a certain extent, the earth will shake and the mountains will shake, and a roaring general eruption will occur. Before the earthquake, subtle changes have occurred within the earth's crust. The heat generated by the friction between the faults is released to the surface, causing abnormal climate in local areas before the earthquake.

According to historical records: Before the 1925 Dali earthquake in Yunnan, "there was no rain for a long time, no cold in the evening, and no dew in the morning";

The 1503 earthquake in Songjiang, Jiangsu, The former "hot wind is like fire".

Geothermal heat is released into the air, causing atmospheric temperature changes, and sometimes forming some unique clouds in the sky. This kind of cloud is a unique phenomenon before an earthquake, so people give it the name earthquake cloud. .

On May 27, around 14:30, Huang Kaiyun, a geography teacher at Hanyin Middle School, discovered three finger-shaped clouds in the sky in the direction of Hanzhong. He introduced them to many colleagues around him (we were also present at the time) and made predictions at the same time. An earthquake was bound to happen, and sure enough, just two hours later, a 5.7-magnitude aftershock occurred in Ningqiang County at 16:37 pm.

4. Physical explanation of abnormal animal reactions before and after earthquakes

Before and after earthquakes, some creatures, such as poultry, toads, ants, snakes, etc., will have abnormal reactions and chaos. Running around in groups, large-scale migration, etc. What happens before an earthquake is called pre-earthquake effect, and what happens after an earthquake is called post-earthquake effect.

The Chinese people have summed up the following experiences in their long-term working life:

Cattle, horses, mules and sheep do not enter the pen, pigs do not eat and dogs bite indiscriminately

Ducks do not enter the water It was noisy on the shore, chickens flew up the trees and screamed loudly

Snakes came out of their holes in the ice and snow, and a large number of toads moved and fled

Rabbits jumped and bumped, and fish jumped in the water in panic

< p> Bees swarm with noisy migration, pigeons are frightened and do not return to their nests

There are many reasons for the abnormal behavior of animals before earthquakes, which still need to be studied. One of the explanations is that animals sense the earthquake. of infrasound waves.

Infrasound waves are produced in destructive activities such as earthquakes, volcanic eruptions, storms, wave impacts, gun firings, thermonuclear explosions, etc., so infrasound waves are also called death waves. Its frequency is less than 20 Hz. This frequency is beyond the hearing range of human ears and cannot be heard by humans, but some animals can perceive it.

For example, before the 7.3-magnitude earthquake occurred in Haicheng, Liaoning Province on February 4, 1975, despite the severe winter weather, insects and butterflies were found.

Accept it, thank you

⑹ Write a 500-word essay about the physics class, interesting physics teacher, and serious work

After entering the second grade of junior high school, it is natural to Added a new course - Physics. Our whole class is looking forward to this mysterious teacher coming to class to see who she is.

The physics lesson started, and the teacher walked in almost stepping on the gun. My deskmate nudged me with his elbow, and I quickly looked away from the physics book. "Beautiful teacher!" my deskmate whispered, and I nodded subconsciously. The physics teacher is a petite young woman with short vertical hair, slightly raised at the end, and delicate cheeks. What I pay more attention to is her dress, but I don’t remember it after so many months. After she taught us for two months, it wasn't until one day that my deskmate said to me in surprise, "Look, the physics teacher finally wore the same clothes today!" I suddenly had three horizontal lines on my face, -_-| ||.

How is the atmosphere in her class? If the Chinese teacher and English teacher are relaxed and lively in class, and the math teacher and politics teacher are serious and old-fashioned in class, then the depressing atmosphere in her class will make you dare not breathe, for fear of being "cut on the neck" the first time you show up.

The fun of my deskmate in the first 30 seconds of physics class is to shout "Wei Lili is here!" With this shout, the scene in our class is spectacular: the boys who are jumping around immediately Rushing back to the seat like an arrow, the girls kept shouting that Wei Lili was coming. At this time, the ping-pong sound of hitting the table and moving the bench made the passing students stop and watch. The representative of the physics department came to the stage with a physics book to read within 3 seconds. After 5 seconds, the whole class returned to calm. There were bursts of reading sounds in the classroom, while my deskmate and I were laughing under the cover of the book.

How is it? I really want to catch a glimpse of the physics teacher! Since we are so afraid of her, is she as beautiful as I say? This is up to you to explore for yourself.

┏ (^ω^)=

⑺ A physicist’s life story is about 500 words

Newton

Newton is Famous British physicist. Mathematician and astronomer. He was born on December 25, 1642 (which happened to be the Christmas of the year that another great physicist Galileo died) in a farmer's family in Woolsthorpool, Lincolnshire, England.

Two months before Newton was born, his father died of illness, and he himself was born into the world less than a month old. Weighing only three pounds. His mother sighed and said: "Well, for such a little one, I could just stuff him into a cup!" The adults were worried that he would not survive. Surprisingly, this weak creature survived tenaciously. Little Newton was raised by his maternal grandmother after he was two years old, and soon went to school in the countryside. He was frail and shy. His academic performance is at the bottom of the class, and he is often bullied by naughty students. But Newton was strong-willed and unwilling to admit defeat. It is said that one time a naughty dynasty named Newton, who was extremely good at homework, kicked Newton in the stomach. Newton was forced to muster up the courage to fight this little bully. Newton secretly determined from then on that he must surpass him in homework. Newton warned himself: "No matter what you do, as long as you work hard, you will never fail." After studying hard, Newton became the first in the class. Newton entered Jingles Middle School at the age of twelve. At that time, he liked to make toys, kites, waterwheels and other things. Youqian is ingenious and willing to use his brain to study, and the kites he made can fly higher than those in the store; he also made an exquisite windmill with a mouse in it, which is called "Mouse Makes a Mill" , even the adults were full of praise after seeing it. When Newton's stepfather died in 1656, he stopped studying and returned to Wuer, Cambodia with his family. In order to alleviate the family's difficulties, his mother asked Newton to do some farm work, herding sheep and shopping. But Newton was obsessed with learning and read while herding sheep. The sheep ate the neighbor's crops and didn't know it. I read books while shopping, but often end up not buying anything. One day in September 1658, the sixteen-year-old Newton conducted a scientific experiment: There was a strong wind that day, and the sand and rocks were flying. Everyone else hid at home, but Newton was the only one running back and forth on the road, sometimes going with the wind, and sometimes against the wind. It turned out that he I am testing the speed difference between the downwind and the headwind, and want to calculate the strength of the wind.

Newton's studious spirit as a boy finally moved his mother and uncle. In 1661, they sent Newton to study at Trinity College, Cambridge University. Two years later, Trinity College established the "Lucas Lectures in Natural Sciences", covering geography and physics. Astronomy and Mathematics. The professor of this lecture was the famous mathematician Barrow (1630-1677). Newton enjoyed these courses very much and studied them eagerly. It didn’t take long for him to stand out. Professor Barrow was worthy of being a versatile "bole". He recognized Newton's extraordinary talent and guided him to study Kepler's "Optics", Euclid's "Elements of Geometry" and other famous works. Newton graduated from University in 1665 with a bachelor's degree and stayed at school to do research. In the summer of this year, the plague broke out in London, and Cambridge University closed in the autumn because of its proximity to the epidemic area. Newton temporarily left Cambridge and returned to Woolsthorpe, where he stayed for eighteen months.

Perhaps it was a "blessing in disguise" that the eighteen months that Newton returned home turned out to be the most productive period in his life. In his own words: "Early in 1665 I discovered... the law (binomial theorem) which reduces the binomial with any exponent into a series. In May of the same year I discovered the tangent method. ... November Discovered the direct flux method (differential calculus). In January of the following year, I discovered the inverse operation of the flux method (integral calculus). In the same year, I began to think about how to extend gravity to the lunar orbit..."

After the plague, Newton returned to Cambridge University. In 1668 he obtained his master's degree. In 1669, Professor Barrow took the initiative to give up his talents and recommended Newton to be the "Lucas Lecture Professor of Natural Sciences". In 1672 Newton was elected as a member of the Royal Society of London. In 1689 he was elected as a member of the British Parliament. In 1696 he became director of the Royal Mint. On November 30, 17O3, he was elected president of the Royal Society. In 1705, the Queen of England named Newton Sir Isaac.

Newton was the greatest scientific giant of the seventeenth century. His lifetime contributions to science spanned the fields of physics, mathematics and astronomy.

Newton's most important achievement in physics was the discovery of the law of universal gravitation and the creation of the basic system of classical mechanics. Thus completing the first major synthesis in the history of physics.

⑻ Write a 500-word review of physics learning

Physics is a newly added course for us in the second grade of junior high school. In the process of learning physics, I think it is important to cultivate good Study habits are very important. When learning physics, you must first learn to preview and consciously cultivate the habit of previewing. The purposes of preview are: to know what to learn; to clarify which parts of the knowledge to be learned are basically understood, and which knowledge needs to be explained by the teacher in class. Secondly, we must learn to listen to lectures with goals and focuses. This is inseparable from previewing. Only when the purpose of previewing is truly achieved can listening to classes be targeted and focused.

Third, we must learn to complete homework independently. The independent completion of homework mentioned here does not simply mean not copying other people's homework, but also means not referring to textbooks or class notes when doing homework. Refers to the ability to complete homework independently. Grasp the three links of preview, lectures and homework in the learning process, and summarize the knowledge learned every week.

Strengthen training and master basic physics skills. In the study of physics classes, there are two basic skills to master. One is the ability to express problems in physical terms and standardize the writing of physical formulas and problem-solving formats; the writing of physical formulas and the problem-solving format of physical calculation problems must be Be standardized and proficient. They are the basis for learning physics well. The second is the basic operational ability of physical experiments. Physics experiment operation skills must be mastered through a large number of hands-on experiments. Only on the basis of mastery can the operation skills be found. When performing experiments, you need to use both your hands and your brain, ask yourself more questions, and then look for ways to solve the problems. You must learn to observe physical phenomena, learn to analyze and summarize based on physical phenomena, and combine existing physical knowledge to draw conclusions.

Pay attention to the basics and focus on understanding physical concepts. In the learning process of physics class, it is important to focus on understanding physical concepts, basic concepts and basic laws. When learning every physical concept and physical law, you can't just memorize it mechanically. You must have imagination and correct thinking ability, and only by mastering it can you truly understand its essence. Therefore, in the process of learning physical knowledge, we must pay attention to the learning of physical concepts in each chapter, and pay attention to understanding every physical concept and every physical law. In the process of solving questions, we must pay attention to the basics, start with basic questions, lay a solid foundation, and then solve difficult problems. In the process of solving the questions, you should use your brain and think more, have a deep understanding of the problem, learn to be flexible, and lay the foundation for future study.

⑼ Physicist After Reading 500 words

Einstein was very playful when he was a child. His mother was often worried about this and repeatedly warned him about what he should do, but it fell on deaf ears to him. In this way, until the autumn when he was 16 years old, one morning, his father stopped Einstein who was going to the river to fish and told him a story. It was this story that changed Einstein's life.

The story goes like this: "Yesterday," Einstein's father said, "our neighbor Uncle Jack and I cleaned a large chimney in the factory in the south. The chimney can only be climbed up by stepping on the steel step ladder inside. . Uncle Jack was in front, and I was behind. We climbed up step by step, holding on to the handrail. When we came down, Uncle Jack was still in front, and I followed him. Later, we climbed out of the chimney. I discovered a strange thing: your Uncle Jack's back and face were all blackened by the soot from the chimney, but there was not even a drop of soot on me."

Einstein's father continued. Smiling and said: "I saw your Uncle Jack's appearance, and thought that I must be just like him, with a face as dirty as a clown, so I went to the nearby river to wash it again and again. And your Uncle Jack, he saw I was clean when I got out of the chimney, so I thought he was as clean as me, so I just washed my hands hastily and went out into the street. As a result, everyone on the street laughed so hard that they thought you were Uncle Jack. He's a lunatic."

After hearing this, Einstein couldn't help laughing with his father. After his father finished laughing, he solemnly said to him, "Actually, no one else can be your mirror. Only you are your own mirror. If you use others as a mirror, you may reflect yourself as a genius."

After hearing this, Einstein suddenly felt ashamed. Einstein left the naughty children. He always used himself as a mirror to examine and reflect himself, and finally reflected the brilliance of his life.

Enlightenment: Compare blindly with others, be satisfied if you think you are smarter than the people around you, or be frustrated if you feel you are not as good as others. How stupid this is! Everyone has different life goals and lifestyles, and you are your most reliable life guide in this world.

⑽ My favorite physical scientist essay 500-word Baidu document

My favorite scientist

When I was very young, I was lying alone under the night sky. The black night sky It is dotted with light and looks very beautiful. Looking at the night sky, I had a dream when I was a child, wanting to see what the sky is like.

When I was in primary school, I learned about the astronomer Zhang Heng.

Zhang Heng (78-139), courtesy name Pingzi, was born in Xi'e, Nanyang (now Shiqiao Town, Nanyang County, Henan Province). He was a great astronomer during the Eastern Han Dynasty in my country and made indelible contributions to the development of astronomy in our country. Contribution; Zhang Heng also showed extraordinary talents and extensive knowledge in mathematics, geography, painting and literature.

Zhang Heng is one of the representatives of the Huntian theory in the middle Eastern Han Dynasty; he pointed out that the moon It does not emit light itself, and moonlight is actually the reflection of sunlight; he also correctly explained the cause of lunar eclipses, and recognized the infinity of the universe and the relationship between the speed of planetary motion and the distance from the earth.

Zhang Heng Observed and recorded 2,500 stars, created the world's first leaky armillary sphere that can perform celestial phenomena relatively accurately, the first instrument for testing earthquakes - the wind seismometer, and also created a compass and an automatic recorder. In order to commemorate Zhang Heng's achievements, people named a crater on the back of the moon "Zhang Heng Crater" and named the asteroid 1802 "Zhang Heng Asteroid" ".

Guo Moruo, a famous Chinese writer and historian in the 20th century, commented on Zhang Heng: "Such a comprehensively developed figure is rare in world history. He has been worshiped for thousands of years, which is admirable. ”

Although I didn’t quite understand why at the time, I also developed a certain curiosity about Zhang Heng. I like to watch the stars, look at the night sky, and like Zhang Heng.

I learned from After reading that article, I counted stars every night and didn’t go to bed until late at night every day.

What was a naive idea at the time is no longer so naive now that I think about it.