Content of handwritten newspaper about popular science knowledge.

In various fields, everyone has seen many classic handwritten newspapers. With the help of handwritten newspapers, we can effectively cultivate our hands-on ability and brain ability. What is the widely used handwritten newspaper? The following is my collection of popular science tips, welcome to share.

1. What is the universe?

A: The universe is the floorboard of everything in the world. It has no boundary, no end, no beginning and no end.

2. How big is the Milky Way?

A: Many stars combine to form a huge galaxy. The galaxy where the solar system is located is called the Milky Way. The Milky Way is like a big discus, with a width of about 80,000 light years, a center thickness of about 1 0.2 million light years, and a total number of stars exceeding10,000.

3. Why can't you see the stars during the day?

A: Because part of the sunlight is scattered by gas and dust in the atmosphere during the day, the sky is very bright and the light radiated by the sun is so strong that we can't see the stars.

4. What celestial bodies are there in the solar system?

A: There are nine planets in the solar system. They are: Mercury, Venus, Earth, Mars, Jupiter, Saturn, Uranus, Neptune and Pluto. In addition, there are many asteroids, comets and meteors in the solar system, and there are 2958 officially numbered asteroids. The most famous comet is Halley's comet.

5. Why do stars have different colors?

A: The color of a star depends on its temperature. Different colors represent different surface temperatures: the surface temperature of blue stars is high and that of red stars is low.

6. What is the brightest star?

A: The brightest star in the sky is Sirius Canis with a magnitude of 1.46. 8.7 light years from the earth.

7. How to find Polaris?

A: It's easy to find Polaris in the sky: first find Ursa major, and then find the Big Dipper. A straight line leads from the two Polaris at the edge of the spoon head, extends past and passes through the Polaris. The distance from Polaris to the spoon head is exactly five times the distance between two Polaris. You can also find Polaris through Cassiopeia.

How high is the blue sky?

A: The "blue sky" is actually the earth's atmosphere. The atmosphere is the air around the earth, which is divided into five layers according to the air density, with a total thickness of 2000-3000 kilometers. But most of the air is concentrated below 15 km from the ground, and the higher the air, the thinner it is. How thick the atmosphere is, how high the blue sky should be.

9. Why is the sky blue?

A: When sunlight hits the earth's atmosphere, blue light is most easily separated from other colors, diffused into the air, and then reflected. The light of other colors has strong penetrating ability, and shines on the earth through the atmosphere, so we can only see the blue light in the sun when we look at the sky.

10. Why is the sky red at sunset?

A: Because sunlight travels a long distance in the atmosphere at sunset. Except for red light, all other colors of light can't travel that far, and they all disappear before they reach our eyes. Only red light runs farthest and can reach our eyes, so we see that the color of the sky turns red at sunset.

1 1. Will the moon shine?

The moon is not a star. It can't shine, but it can reflect sunlight. Although only 7% of the light it reflects can reach the earth, it is enough to light up the night on our earth.

How many stars can we see?

A: We can see 7,000 stars from the earth with the naked eye, but because the earth is round, no matter where we stand on the earth, we can only see half of the sky, and the stars near the horizon are not clear, so our naked eye can only see about 3,000 stars.

13. How high is the sun?

A: The central temperature of the sun is as high as192,000,000℃ and the surface temperature is 6000℃. But because the sun is far away from us, with1.500 million kilometers, we don't feel so hot.

14. Why does the earth turn?

A: Because the earth has gravity, it is precisely because of this gravity that the earth turns. The rotation speed of the earth is per hour 1700 km, that is, 470 meters per second; The revolution speed is about 29.8 kilometers per second.

15. Why is the sun white at noon?

Answer: Because at noon, the sun can shine directly on the ground, unlike things on the ground (such as mountains, trees, buildings and turbid air) in the morning and evening, it is still the original white light, which makes people afraid to open their eyes.

16. Why is it so difficult to walk on the moon?

A: Because the gravity on the moon is very small, it is easy to slip when walking, and only 20 steps can be taken in one minute. If you walk in a hurry, it's easy to fly. Once it flies, it is unstable for a long time. Therefore, it is very difficult to walk on the moon.

17. Why doesn't the earth shine?

A: Because the temperature of the earth is relatively low, the hottest place (the core) is two or three thousand degrees, unlike the temperature of the sun, which will cause thermonuclear reaction, so the earth will not shine.

18. Why can't people feel that the earth is turning?

A: Because the earth is very big and rotates smoothly, we are also following it. We take ourselves as a reference, so we can't feel the earth spinning.

What is the thunder?

A: This is a natural phenomenon that negative electricity meets positive electricity. When it rains, some clouds in the sky are positively charged and some are negatively charged. When two clouds meet, they will discharge, emit bright and bright lightning, and at the same time release a lot of heat, which will make the surrounding air heated, expand and make a loud noise. This is thunder.

20. What is a meteor shower?

A: There are many small celestial bodies in the universe flying at their own orbits and speeds. Some blew themselves up and some collided with other celestial bodies. But they kept flying. When their orbits meet the earth's orbit, they fall to the ground like raindrops. This phenomenon is called meteor shower.

2 1. Why did the cloud go?

A: Clouds are water vapor floating in the air. Air is also constantly flowing in the air. The flow of air is the wind, which blows away the clouds. The faster the air moves, the faster the cloud moves.

22. Why can an airplane fly into the sky?

A: An airplane has two wings. Just like the wings of a bird, it also has a propeller. The wing can generate lift and lift the plane into the air; Propeller can produce the ability to push the plane forward. Therefore, the plane can fly into the sky like a bird.

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The contents of handwritten newspaper about the popularization of life science.

1. Why should traffic lights be installed on the plane?

On a clear night, if you hear the "rumble" of the plane, children like to watch it. At this time, we can see red, green and white light moving slowly in the sky. This is the navigation light on the plane. Planes fly at night. In order to avoid collision accidents, navigation lights are installed on the wing and tail of the aircraft. This is the same as installing traffic lights at intersections in big cities to direct passing vehicles and avoid traffic accidents. From the pilot's position, the red light is installed at the tip of the left wing; The green light is installed at the tip of the right wing; White light is installed at the tail of the plane. If the pilot sees red and green lights in the night flight, he will know that an airplane is coming towards him. If it is at the same altitude as his plane, it may collide and must be avoided. If he only sees a light, it means that the coming plane is on his left or right; If you see three light areas at the same time, it means that the other party is flying above or below you. There is no danger of collision in either case.

2. Why does a flat ping-pong ball bulge after scalding with boiling water?

When children play table tennis, sometimes they accidentally step on it. As long as it is scalded with boiling water, the table tennis will become round again. What is the reason? Table tennis is full of air. When it is trampled flat, the air is compressed and cannot retreat. As soon as boiling water is scalded, the air in the table tennis ball expands when heated, and the flattened place is propped back to its original shape.

3. Why can you see things far away with a telescope?

A telescope has two convex glasses, called convex mirrors. The front piece is large and called the objective lens; The small one in the back is called the eyepiece. The objective lens can move the image of the distant scene to the eyepiece. When you look at the eyepiece, you can look at what is in front of you like a magnifying glass, so that the distant scenery looks like it is near.

4. Why can an eraser erase pencil words?

Pencil lead is made of graphite and clay. Graphite is soft, it is colored ink, and it is easy to adhere to paper, so it can write. Rubber is very soft, with high friction and certain viscosity. When rubbing on paper, it can stick the written pencil handwriting without damaging the paper, because some rubber can erase the pencil handwriting. If you write with a ballpoint pen, the pigment will penetrate into the paper and will not be easily erased.

5. jiaozi is ready, why does it float?

Raw jiaozi is heavier than water. Put it in the pot and sink it first. Cooked dumpling stuffing and dumpling skin expand when heated, and become plump, buoyant and floating. So are dumplings and wonton. When they float, they are cooked. It's the same as cooking jiaozi.

6. When you knock a gong, why does it stop ringing when you press the gong's heart?

Before you knock the gong, you won't feel any vibration if you tap the gong surface with your hand model. However, when the gong rings, you will feel the vibration of the gong face when you gently mold it. The gong sound we hear is the vibration of the gong surface, which sends out sound waves and reaches our ears through the air. If you press your hand on the center of the gong, it will stop vibrating, make no sound waves, and of course it will not ring. Other things vibrate and make sounds.

7. Chopsticks are inserted in a glass filled with water. Why do they look bad?

Put chopsticks in a glass filled with water, it looks like it is broken; I picked up the chopsticks and looked at them. Fortunately, I didn't even bend. What's going on here?

This is just a trick. Light passes through transparent things, such as glass, air and clear water, but the direction and speed of progress are changing. In air, light goes straight ahead; But through other transparent things with different properties, we have to change direction and turn a corner, which is called refraction. In addition, light travels faster in air and slower in water. Put chopsticks in a cup filled with water. Chopsticks are half in water and half in air. The light reflected by chopsticks in our eyes has different speed and direction when it passes through water and air. It seems that the chopsticks are broken.

8. Why are things made of iron colder than those made of wood in winter?

In winter, it is much colder for children to touch the iron handrail of the slide on the playground than to touch the wooden boat or wooden horse. Why is this? In fact, their own temperatures are the same, so people will think that iron is colder than wood, because iron transfers heat much faster than wood. We hold the iron handrail of the slide and feel cold and stinging because the heat in our hands quickly spreads to the whole iron handrail and is lost. When you touch a wooden boat or wooden horse with your hand, the heat in your hand only reaches a small part of the wood you touch, so it is not easy to spread, so you won't feel as cold as touching iron.

9. In winter, why do we exhale white gas in our mouths?

When the weather is cold, we can see a white gas by breathing gently through our mouths. In summer, you exhale a lot, but you can't see white gas at all. Then why?

Our normal body temperature is about 37 degrees, and the temperature in winter is much lower than our body temperature. The hot air we exhale contains moisture. When it comes into contact with the cold air outside, it will condense into tiny water droplets, which look like bursts of "white smoke". In summer, the weather is hot and the temperature is high, so the gas exhaled from our mouths will not condense into small water droplets, so we can't see "white smoke".

10, the water in the glass bottle is frozen, why did it break?

In winter, when the temperature drops below zero degrees Celsius, water will freeze. At this time, if you put water in a glass bottle and put it outdoors, the water in the bottle will also freeze. The lower the temperature, the thicker the ice, and finally the glass bottle broke. This is because water has a "strange temper". When it is cold enough to freeze below freezing temperature, the volume will not shrink, but will increase. Therefore, the glass bottle will burst.

1 1, water is hot, why does it make noise?

When boiling water, first heat the water at the bottom, and small bubbles will appear at the bottom of the pot, making a slight hiss. The more water burns, the hotter it gets. Small bubbles leave the bottom of the pot and rise, but they burst before reaching the water surface, causing air vibration. The kettle began to hum, with a sharp tone, as if to tell you; The water is boiling.

After the water is boiled, there are many big bubbles, which will not burst until it rushes out of the water surface, causing greater vibration of the air and making a "poop-poop" sound with a relatively low tone. So some people say; "Boiling water doesn't boil, boiling water doesn't ring". In fact, water is hot to a certain extent, but the tone is different. Experienced people can judge whether the water is boiling according to the sound made by the water shell. Children can observe for themselves and see if this is the case.

12. Why is the freezer in the refrigerator located on the top floor?

Because cold air sinks and hot air rises, the freezer of the refrigerator is located on the top floor, and the surrounding air sinks due to cold, and the hot air rises to supplement the freezer, then sinks after cold, and the hot air below rises again-such cold and hot convection, up and down, back and forth, will make the temperature in the whole refrigerator drop, which can achieve the best effect on frozen food. If the refrigerator is located at the bottom of the refrigerator, the air it cools can only stay at the bottom of the refrigerator, so the air in the upper layer of the refrigerator can't be cooled down, and the food placed inside can't achieve the freezing effect. Similarly, if you use ice to cool food, you should also put ice cubes on it.

13. Why is the water in the toilet tank not full?

There is a very delicate mechanism in the water storage tank of the toilet. One end is a hollow ball and the other end is a piston. When the water in the water tank is loaded to a certain height, the hollow ball is lifted by the buoyancy of the water, and the piston at the other end will press down to block the water inlet, so that the water will no longer flow into the water tank. When we need to flush feces, as long as we press the wrench and the connecting rod lifts the rubber bowl blocking the water outlet, water will rush out of the water storage tank and wash away feces. When the water in the water tank is used up, the hollow ball will sink to the bottom of the water tank, and the intake piston at the other end will be lifted to let the water flow submerge the water tank. The hollow ball will slowly rise to the specified height with the water surface, and the water inlet will automatically close.

In addition, there is an overflow pipe in the water tank. If the height of the hollow ball is not appropriate and too much water is injected, the excess water will flow away from the overflow pipe instead of overflowing the box and flowing to the ground. In this case, as long as the position of the hollow ball is adjusted to make the water surface lower than the overflow pipe, water will not be wasted.

Why can electric fans make people feel cool?

In summer, when the electric fan turns, a cool wind blows gently, which makes us feel much cooler. Did the electric fan cool the air? No, if you blow the thermometer in front of the electric fan, the temperature will not drop even if you blow it for fifty minutes. This shows that electric fans can't cool the air.

The electric fan makes people feel cool, mainly because the blades of the electric fan rotate, resulting in wind, which drives away the hot air around our bodies and allows cooler air to flow, making us feel cool and breezy. Air flow accelerates the evaporation of skin moisture, and the more heat our body loses, the cooler we feel.

15, why do you sleep with a pillow?

Some children sleep without pillows. They put down their pillows or put their heads under them. In this way, after getting up, the eyelids are often swollen. The spine of human neck is naturally curved. If you don't use a pillow when sleeping, your head position is too low, and there is nothing to rely on under your neck. The muscles and blood vessels in your neck are very tight, which will affect the blood circulation in your head. After a long time, I feel that there is acetic acid in my neck, and I wake up dizzy and my eyelids are swollen. So you must sleep with a pillow. With a pillow, you can relax your neck muscles when you sleep, feel comfortable when you lie down, breathe smoothly, fall asleep easily, and wake up without feeling sore.

16, why do you have to cover your stomach when you sleep in summer?

In hot weather, many children go to bed naked, wearing only a pair of underwear. Remember; You have to cover your abdomen with a towel or a quilt. Why?

Because when people sleep, muscles will relax and the activities of many organs of the body will slow down. Their body temperature is lower than when they wake up, and they are easy to catch a cold. The abdominal muscles are thinner, especially the abdominal muscles around the navel. When the stomach is cold, the peristalsis of the intestine will increase, so that the food residues that are not fully digested and absorbed in the intestine will be excreted in advance with a lot of water. At this time, the stomach will purr, causing abdominal pain or diarrhea. Pay attention to keep warm when sleeping. Even in summer, cover your stomach with a towel or a small quilt when you sleep at night.

17. Why do you feel hot after taking a bath with cold water?

There are many pores in our skin. If we take a bath with warm water, the pores of sweat glands will expand, sweat will be discharged more smoothly, and the heat in the body will dissipate quickly, so we will feel cool and comfortable after taking a bath. On the contrary, bathing with cold water will shrink the pores of sweat glands, excrete less sweat, and the heat in the body cannot be distributed. Although taking a cold shower will make you feel cold, after taking a shower, the surrounding temperature is higher than the temperature of the skin surface, so you will feel warm.

18. In summer, why is it cooler to wear light clothes than dark clothes?

Let's do a small experiment first; Find a piece of black cloth and a piece of white cloth, put a piece of ice or half a popsicle of the same size in the sun. After a while, we went to see which piece of ice melted, and the result was that the black cloth wrapped it melted first. This is because the black bag absorbs the sun's light and heat easily, and the white bag reflects part of the sun's light, so the ice wrapped in black cloth melts first.

Similarly, people wear light or white clothes in summer. It can reflect part of the sunlight that shines on it, making people feel cool. Wearing black or dark clothes absorbs sunlight and makes people feel sultry.

19, wear three thin sweaters or one thick sweater to keep warm.

Some children are afraid of trouble and don't want to wear more clothes in winter. A child said to his mother; "You put three sweaters together and weave a sweater with three times the thickness. I will only wear one sweater, and my mother can save a lot of time knitting sweaters. " But mom didn't agree. Is it warmer to wear three sweaters or a sweater with three times the thickness?

The child's advice seems clever. In fact, wearing a sweater three times as thick is not as warm as wearing three thin sweaters. Because the sweater itself can't increase our temperature, it is mainly kept warm by the air hidden between the wool, so that the hot air on our bodies is not easy to lose and we feel warm. The more air there is in a sweater, the warmer it is. Wear three thin sweaters and three layers of warm air; No matter how thick you wear one, there is only a layer of warm air. So wearing three thin sweaters is warmer than wearing a sweater with three times the thickness.

20. The fluorescent lamp is broken. Why do people leave at once?

If the fluorescent tube breaks down accidentally, adults and children should leave at once. Because fluorescent tubes are full of toxic mercury vapor, people inhale this vapor, which is harmful to the nervous system and digestive system. Adults should wait until the mercury vapor runs out before cleaning the broken lamp.