Does Baidu know what a good answer is?

The so-called high-quality answer refers to the answer that can be called a model in knowing the answer.

They have the following characteristics: strong knowledge and professionalism, accurate, detailed and professional answers, high-quality answers also have corresponding requirements for the content of questions, standardized wording of questions and answers, beautiful typesetting and strong readability.

Standards and examples are as follows:

A good answer includes two parts: question and answer. Only when the questions and answers meet the standards can they become good answers!

Ask for detailed requirements

Questions should be written in a standard, clearly expressed, knowledgeable, professional and not personalized.

Answer detailed requirements

The answer is accurate, comprehensive and detailed, knowledgeable and professional, and easy to read.

example

Why is the sky blue?

Why is the sky blue? The reason is not like the common answer, because "there will be a lot of tiny dust, water droplets, ice crystals and other substances in the air." When sunlight passes through the air, colored light with short wavelength such as blue, purple and indigo is easily blocked by particles suspended in the air, thus scattering light in all directions and making the sky appear blue. "

Compared with the wavelength of visible light (about 400 nm to 700 nm), particles such as dust and water droplets in the air are much larger than the wavelength of visible light in sunlight, so when sunlight meets these particles, it will reflect in different directions. However, this reflection has the same effect on light with different wavelengths (or colors). In other words, white light containing all colors will still be reflected by particles such as dust. For example, PM2.5 is the pollution caused by suspended particles with a particle size of ≤2.5 microns in the air, so when the air pollution index is high, the sky will be white.

Then why is the sky blue? In fact, there are a large number of particles in the air whose size is smaller than the wavelength of visible light, that is, many gas molecules in the air, such as oxygen and nitrogen molecules, with a "diameter" of about 0.3 nm. When these gas molecules are encountered, they will absorb some photons. After a while, the molecule will release another photon. The emitted photons are the same color as the absorbed photons, but the direction has changed. Although photons of all colors are absorbed, photons with higher frequency (blue) are more easily absorbed than photons with lower frequency (red). This process is called Rayleigh scattering, which is named after the British physicist Sir John Rayleigh, who first described this process in the 1970s.

Then, blue light is more likely to Rayleigh scatter with air molecules, and how can it produce blue sky? Let's make a simple hypothesis. If there were no air, what color would the sky be? Although most of us have never been to space, we can see from the documentary of Apollo landing on the moon that even if the sun shines in the sky, the sky is still black.

Because there is Rayleigh scattering in the air, the situation is completely different. On the way of sunlight spreading in the atmosphere,

Blue light is more prone to Rayleigh scattering, and its deflection direction is different from the original direction of sunlight. Therefore, even if we don't look directly at the sun, but look in other directions of the sky, there are always photons scattered by air molecules (more blue light) that enter our eyes, so we see the blue sky.

The application conditions are as follows:

Every Monday, "Baidu knows" opens the self-recommendation post of that week, as long as you recommend yourself in the following format. The format requirements are as follows:

A. sponsor's ID:

B. Specific classification of self-recommendation:

C. Answer link:

Friends who have successfully recommended themselves shall be reviewed by the Knowledge Promotion Committee, and within 5 working days, representatives of the Committee will reply and inform them of the review results and opinions.

Baidu Know will also publish a bulletin board with high-quality answers every week to show the questions and answers rated as high-quality answers for your reference.

No matter the questioner or the respondent, please be responsible for the content and spread better knowledge with Zhihu. We look forward to more standardized and clear questions, and we look forward to more accurate, comprehensive and professional answers based on our own knowledge, experience or opinions, so as to help questioners, questioners and respondents work together to spread better knowledge.

The evaluation and reward are as follows:

evaluate

People with strong professional ability in the corresponding fields will be given the right to judge high-quality answers, and users who have contributed more high-quality answers in various categories in the station will be judged together until well-known experts and scholars in the corresponding fields continue to be invited.

4 rewards

High-quality answers will be specially displayed on the Q&A page, and will be given priority by the official to the channels such as the wonderful recommendation on the homepage;

Contributors who answer well will be rewarded with 50 experience values and wealth values;

Later contributors will have greater voice and influence, and will get more privileges, such as high ID and bold fonts.

Hope to adopt!

References:

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