Why are there rainbows on sunny days?

Rainbow is formed by the scattering and reflection of sunlight on small round water droplets in the air. When sunlight enters the water drop, it will be incident at different angles at the same time and reflected at different angles in the water drop. The reflection of 40 to 42 degrees is the strongest, which produces the rainbow we see. When this reflection occurs, sunlight enters the water drop, refracts once, then reflects on the back of the water drop, and finally refracts again when it leaves the water drop. Because water has a dispersive effect on light, the refractive index of light with different wavelengths is different, and the refractive angle of blue light is greater than that of red light. Because light is reflected in water droplets, the spectrum seen by the observer is reversed, with red light at the top and other colors at the bottom. In fact, as long as there are water droplets in the air and the sun shines behind the observer at a low angle, an observable rainbow phenomenon may occur. Rainbow usually appears in the afternoon, when the rain clears. At this time, the air is less dusty and full of water droplets, and one side of the sky is dark because of rain clouds. However, observers can see the sunlight without being covered by clouds above or behind them, so rainbows are easier to see. Another place where rainbows are often seen is near waterfalls. When the weather is clear, you can spray water or mist into the air with your back to the sun, or you can make rainbows artificially. The size of water droplets in the air determines the bright color and width of the rainbow. When the water drops in the air are large, the rainbow is bright. Also relatively narrow; On the contrary, if the water drops are small, the rainbow will be light and wide. We can't see the rainbow when facing the sun, but only when facing the sun, so the rainbow appears in the west in the morning and always in the east at night. But we can't see it. We can only see it from the sky by plane. The appearance of rainbow is related to the weather change at that time. Generally, we can infer whether it was sunny or rainy from the position where the rainbow appeared in the sky. When there is a rainbow in the east, it is not easy to rain locally, but when there is a rainbow in the west, it is likely to rain locally. The visibility of rainbow depends on the size of water droplets in the air. The bigger the water drop, the brighter the rainbow, and the smaller the water drop, the less obvious the rainbow is. Generally, in winter, the temperature is low, there are few water droplets in the air, and there are few opportunities for showers, so rainbows are generally not seen in winter. The optical principle that causes rainbows often sees two rainbows appear at the same time, and a concentric but dark secondary rainbow (also called neon) appears outside the ordinary rainbow. The secondary rainbow is formed by two reflections of sunlight in water droplets. The strongest reflection angle of the two reflections occurs at 50 to 53, so the position of the secondary rainbow is outside the main rainbow. Because there are two reflections, the color sequence of the auxiliary rainbow is opposite to that of the main rainbow, with the outer side being blue and the inner side being red. In fact, the auxiliary rainbow must follow the main rainbow, but sometimes it is invisible to the naked eye because of the low light intensity. Double rainbow over Scotland 1307, it was suggested in Europe that the rainbow was caused by the refraction and reflection of the sun light by water droplets. Descartes found in 1637 that the size of water droplets does not affect the refraction of light. He experimented by injecting water into the glass ball and got the refractive index of water to light. He mathematically proved that the main rainbow is caused by reflection at the water point, while the auxiliary rainbow is caused by two reflections. He calculated the angle of the rainbow accurately, but failed to explain its colorful colors. Later, Newton discovered all the optical principles of rainbow formation after scattering sunlight into color with a glass rhombus.

Why do rainbows appear on sunny days?

LS is wrong

Rainbow is formed by the refraction of sunlight by larger water droplets in the air.

Sometimes there are no precipitation clouds on the horizon, but there are strong winds in the middle and lower (non-ground) atmosphere, which will bring raindrops from distant precipitation clouds near where rainbows will appear. If the surface is very hot and the updraft is strong enough to contain water droplets, but it cannot evaporate quickly, then it is possible to see a sunny rainbow with angle and position factors.

Why do rainbows appear on sunny days in Shanghai?

Many netizens sent pictures to Xiao Bu this morning, saying that they saw a beautiful rainbow in the sky around 5 or 6 in the morning! Did you see it or missed it in your sleep?

Many photos of Zhang Caihong sent by netizens and experts from the Municipal Meteorological Bureau explained in detail, "Why is there a rainbow on a sunny day?"

Zhang, the chief service officer of the Municipal Meteorological Bureau, explained that the rainbow is related to the water vapor in the air and the height of the sun, that is, the incident angle of light. It doesn't have to rain, for example, you can see it near the fountain near the waterfall. Recently, it is the rainy season, and the air is full of water vapor. Since 5 o'clock, there has been weak rainfall, high humidity and sufficient water vapor in the northwest and southwest of our city.

But even so, the sun needs to be at the right height, and the rain just stopped. If the rain stops for a long time, the water droplets are not the right size and cannot be seen. Therefore, it is also very lucky to see the rainbow.

Why do rainbows appear on sunny days after rain?

Natural phenomenon, after the rain, the air humidity is high and there is much water. When the sun shines on the water droplets in the air, it will refract and reflect the seven-color arch spectrum, thus forming a rainbow, which is why the color order of the rainbow is so unified and fixed.

Please accept it, thank you!

Why do rainbows appear on sunny days?

After the rain, there will be mist in the sky and the sun will appear. When sunlight is refracted by water, a beautiful rainbow will appear!

Why do rainbows appear in sunny weather?

In fact, as long as there are water droplets in the air and the sun shines behind the observer at a low angle, an observable rainbow phenomenon may occur. Rainbow usually appears in the afternoon, when the rain clears. At this time, the air is less dusty and full of water droplets, and one side of the sky is dark because of rain clouds. However, observers can see the sunlight without being covered by clouds above or behind them, so rainbows are easier to see. Another place where rainbows are often seen is near waterfalls. When the weather is clear, you can spray water or mist into the air with your back to the sun, or you can make rainbows artificially.

What is the rainbow on a sunny day?

Rainbow is caused by dispersion and reflection caused by sunlight shining on small round water droplets in the air. When sunlight enters the water drop, it will be incident at different angles at the same time and reflected at different angles in the water drop. The reflection of 40 to 42 degrees is the strongest, which produces the rainbow we see. When this reflection occurs, sunlight enters the water drop, refracts once, then reflects on the back of the water drop, and finally refracts again when it leaves the water drop. Because water has a dispersive effect on light, the refractive index of light with different wavelengths is different, and the refractive angle of blue light is greater than that of red light. Because light is reflected in water droplets, the spectrum seen by the observer is reversed, with red light at the top and other colors at the bottom.

What do you mean there will be a rainbow soon on a sunny day?

Rainbows all appear on sunny days, but not every sunny day has rainbows, which shows inevitability and contingency. For example, success must be the result of hard work, but hard work may not be successful.

Why is there a rainbow in the sky! Urgent! !

In summer, after the rain, the dark clouds fly away and the sun reappears. In the sky opposite the sun, there will be a semi-circular rainbow.

Rainbow is formed because sunlight is emitted in the air and refracted into water droplets.

We know that when sunlight passes through the prism, the direction of the foreground will be deflected and the original white light will change.

The line is broken down into seven color bands: red, orange, yellow, green, cyan, blue and purple.

After the rain, there are many tiny water droplets floating in the air. When the sun shines on them, they will refract and disperse.

Into seven colors of light. Many small water droplets refract sunlight at the same time, and then reflect into our eyes, and we will see one.

A semicircle rainbow. The ribbons of the rainbow are distinct, and the red ones are on the outermost side, followed by orange, yellow, green, cyan, blue and purple.

Color.

The size of water droplets in the air determines the bright color and width of the rainbow. When the water drops in the air are large, the rainbow is bright. also

Relatively narrow; On the contrary, if the water drops are small, the rainbow will be light and wide.

We can't see the rainbow in front of the sun, but we can see the rainbow with our back to the sun, so the rainbow in the morning appears in

In the west, the rainbow at dusk always appears in the east. But we can't see it. We can only see it from the sky by plane.

The appearance of rainbow is related to the weather change at that time. Generally, we can infer from the position of the rainbow in the sky that it will appear at that time.

It is sunny or rainy. When there is a rainbow in the east, it is not easy to rain locally, and when there is a rainbow in the west, it may rain locally.

Very sexual.

The visibility of rainbow depends on the size of water droplets in the air. The bigger the water drop, the brighter the rainbow, and the smaller the water drop, the less obvious the rainbow is.

Generally, in winter, the temperature is low, there are few water droplets in the air, and there are few opportunities for showers, so rainbows are generally not seen in winter.