General scientific knowledge in everyday life, how much do you know? Share eleven life science knowledge today

#科学every day# In ordinary life, we always hear some information about science, but what you don't know is that some of this scientific knowledge is not true, let's see in editor below. Let's see what we have.

Previous mobile phones did have such a claim, and it's not a paradox but a fact, but times are changing and technology is also improving. All mobile phones we use today are lithium batteries, and inside smartphone there is a charging protection chip that automatically turns off power when fully charged. Thus, this statement is not valid nowadays. Previous mobile phones did not have a fully charged power off function, which did cause problem of battery swelling. Now you only need to recharge when you go.

Many people may not have heard this statement, but it is not entirely false. Because x-rays can really damage hard drives, but intensity of x-rays is very high. The ability of a hard drive to withstand x-rays is much higher than that of human body. Therefore, when people go through security checks or health checks in hospitals, nothing happens. How can there be problems with a hard drive? On surface of earth, we in principle cannot encounter such strong rays, so this problem should not be worried at all.

The current computer and mobile phone actually have something in common, especially Windows 7 system. After restarting computer after a long time, speed will increase significantly. This is because software is not fully closed in background. This is not a disadvantage, but in order to open faster next time. Moreover, even though computer is in sleep mode, when not in use, power supply is always on. While it is on, life of computer is reduced. This is an indisputable fact. Therefore, it is best to switch off computer when not in use.

IOS system optimization is really very good, and security is also very high. But it is unrealistic to say that it does not have viruses and its security is based only on Apple's own app store. If phone is jailbroken, it is actually same as an Android phone, or even worse than an Android phone. Moreover, there is nothing worth hacking on personal mobile phones: risk and cost of an intrusion can be much higher than cost of your mobile phone. Simply put, your cell phone is not worth being hacked by others because it is worth nothing.

Everyone has seen properties of photo. You can right click on computer to display properties. They are also available on mobile. It will show characteristics of photo, like 500 x 300 etc. but do you know units behind it? That's right, it's just a pixel. A pixel is just a unit of measurement. What does it have to do with photo quality? The cell phone camera is just a small hole image processing hardware, and most important thing is to look at cell phone sensor. I think you have already seen that quality of 12 million pixel photos is actually better than 48 million pixel photos. It's sensor's fault, but by disguising it, higher pixels can actually improve clarity of a photo, but that's an illusion. For example, a mobile phone has a resolution of 1280x720, but what if photos taken by your mobile phone are much larger than this size? This is compression, large photos compress small photos and resolution is increased. But essentially, it's all same, but you don't have a bigger device to play it.

6. Does Wi-Fi radiation harm body?

First, ask everyone question: does sun have radiation? I believe your answers should be yes, Wi-Fi radiation is much less than that of sun, have there been any incidents after we have been exposed to sun for so many years? It's true that Wi-Fi has radiation, but it's within range that human body can withstand, and it's optimistic about resistance rather than endurance. In everyday life, you don't need to worry about Wi-Fi radiation, just use it with confidence. Moreover, even if it is, you do not need it? We are now basically "soaked" in Wi-Fi signal every day. If you don't believe me, turn on wireless function of your mobile phone, and if you can find Wi-Fi, then there is Wi-Fi. Are you still not well?

Many people may not understand this. The magnetic field of a high-speed rail is actually an open magnetic field, which is different from magnetic field of a closed magnetic induction. Its radiation dose is very small and within range that human body can resist, let alone harm human body. In addition, earth itself also has a magnetic field. Since we are alive, raised by earth, we can adapt well to current environment.

I don't know why such pseudo-common sense can exist for so long, how many hot strips and instant noodles a factory has to produce? They can be many, many, even countless. If workers are allowed to step on it, how many workers and how much space will they need? What's better than a car? It must be a car, and thousands of instant noodles pass by every day. Even if you painted it with black ink, it must be clean. And truth is that purity of instant noodles is beyond your imagination.

The current specifications of mobile phone is 5V input voltage, 4.2V output voltage, which is standard, and chargers have also reached same level, they are all 5V, there may be higher voltage fast chargers, but It is possible Controlled, when charger does not recognize fast charger, output voltage is 5V, and current does not exceed 2A. Why can not use a non-original charger. Just charging speed is slow.

The editor personally tested air conditioner, one of them was used normally during day and rested for eight hours every day. Another worked 8 hours a day with breaks. Simulating a shutdown situation when they are not in use causes electricity bill of two air conditioners to be 4 times ratio. The first costs 100 yuan, second costs 400 yuan. (Regardless of low peak or peak value, only practical) And these sensitive electrical appliances often start instantly with power that can reach 3-9 times rated power. What is this concept? Under normal conditions, it is better not to turn off air conditioner if you leave room for less than 3 hours.

Have you heard of barrel principle? Computers also follow this principle. The performance mainly depends on equipment with shortest board. The CPU is powerful, but performance of other equipment cannot keep up with it, so overall performance of computer will not be high. There are relatively few people with such thinking now, because everyone knows about this aspect of knowledge.

Good! The above is full contents of this release, comments are welcome. (Wen\Ahui Note: Without permission, no!)