"I just say that my hair loss has nothing to do with staying up late!" | No.324
Author:Institute of Physics of the Ch Time:2022.09.10
My mother always said that I had a hair loss because I stayed up late, so I went to bed early, but I felt that I did n’t think of physics because I learned physics, so I said that staying up late would lose hair? The ice cubes in Q1 fast food restaurants are not cubes of the rules. There is a groove in one side. What is the reason? By Anonymous Answer:
The reason is actually caused by the shape of the ice mold. The square ice cubes in the fast food restaurant beverage are made in batches with ice -making machines. Among them, the core part of the refrigeration is a square -like ice groove.
If a row of ice grooves look at it from the side, its metal partition is the part of the heat transfer with water, so the heat will be passed in accordance with the method shown in the figure below.
Therefore, it is not difficult to imagine that ice grows from the metal crickets at the side and the bottom to the middle and above, so a groove -like ice cubes that are common in fast food restaurants are formed.
Reference materials:
Search results_ Why does KFC ice cubes have a recessed side?
Working principle of ice making machine
Finally the ice cubes are free ~~
by Yunkai Leaves
Q.E.D.Q2 What is the difference between air conditioning cooling and dehumidification function? Which is more power -saving? By Anonymous Answer:
You can understand the dehumidification as a refrigeration youth version. Its working goal is to condense the inhaled air out of liquid water, but it does not require so cold than the refrigeration, so generally, dehumidification will save more power.
The working principle of dehumidification and refrigeration is the same. The refrigerant in the condensation tube will be reduced by the expansion valve to reduce the pressure in the indoor. This process absorbs heat, and then flows to the outdoor compressor to press liquefaction. This process is inspired. When the refrigerant absorbs heat indoors, the water vapor in the air will encounter cold liquefaction. These liquefied condensation water will be collected and discharged, which is the origin of air conditioning water. After the whole process, it not only made cold, but also in addition to wetness.
Because the temperature of the indoor condensation tube is needed to liquefy the water vapor, the temperature required by the dehumidifier mode is not so low, and the working time interval of the compressor can be longer. Therefore, as far as most of the air conditioners I found, setting the dehumidification mode is more power -saving, but some manufacturers have set more fierce work targets for dehumidification, but consume more power in the dehumidification mode.
In addition, there are some high -end air -conditioning supporting the heat and dehumidification, that is, heated the dehumidified air to provide more comfortable dry and gentle air, but this is even more electricity.
Reference materials:
The difference between air -conditioning dehumidification and refrigeration?
BY Shepherd
Q.E.D.Q3 Why does it go to stay up at night? By Anonymous Answer:
Staying up late does not necessarily lead to hair loss. For example, the editor who is staying up late to write answers, the hairline is very healthy (proud face.jpg).
The human body drops 50 to 100 hair every day. This hair loss is falling off because the hair reaches the rest period during the normal growth cycle, called physiological hair loss. At the same time, the corresponding number of hair will enter the growth period of hair. The two maintain dynamic balance, and the hair will not decrease.
When the number of hair falls off more than 100 daily, there is the effect of non -biological hair loss, which is the source of hair loss that we mainly discuss. There are five main reasons: male hormone hair loss (also known as fat -shaped hair loss), immune deficiency hair loss (alopecia areata), damaged hair loss, nutritional abnormal hair loss, and medicinal hair loss.
The effects of staying up late on hair loss are mainly related to the first two types of reasons.
On the one hand, long -term staying up will cause the hormone level imbalance in the body, and the ratio of the dual -hydrogen testosterone (DHT) of therogens metabolites, and the scalp hair follicles will shrink in advance under DHT stimulation, resulting in hair loss. Of course, a certain amount ofrogens will also produce a certain amount ofrogens under normal circumstances, so even if the rules of schedule, some people will gradually start hair loss after sexual maturity.
On the other hand, staying up late is not a choice of itself. The essence behind it is the issue of spirit, emotion, and pressure. These mental stress may induce alopecia areata. Studies have shown that stress will lead to hair loss, that is, the hair will enter the period from the growth period to the rest period, which will cause hair loss.
Therefore, if you do n’t have to stay up late, please keep a positive and optimistic attitude, even if you are unwilling to be in other aspects, at least you can keep your hair. (Manual dog head)
Reference materials:
[1] Yu Xiaogan, Ma Yuchen, Ding Wenyu, Hu Yiqiong, Jia Yan, He Congfen. Non-physiological hair loss types and its mechanism research progress [J]. Daily chemistry industry, 2021,51 (11): 1118-1124.
Will stay up all night?
Will stay up all night?
BY Le Superman
Q.E.D.Q4 tires have gas and gas, will it affect the speed of electric vehicles? BY onion Answer:
Let's talk about the conclusion first.
When the tire is moving forward, the friction force is not sliding and friction, but rolling friction (also static friction). The friction force is not the main factor that affects the speed, but the torque. When the tire is rolled forward, the contact squeezing between the tire and the ground causes the support to do not vertically upward along the axis, and it will generate certain offset to form a torque. From the figure below, it can be seen that this torque is opposite to the rotation direction of the forward, so it is the resistance of the resistance.
The torque is represented by M, m = lxf. The size of the torque is the product of the force F and the force arm. The force arm in the figure is the distance between the red arrow and the yellow midline. When the tire is not stagnated, the area of contact with the ground will increase the position of support when the car moves forward (the principle, can you imagine whether your feet are slowly lifted from the heel, To the toes ~).
Because the weight of the electric vehicle itself has not changed, the supporting force is unchanged, and the position of the force arm becomes longer and the resistance torque is further increased.
According to the power formula, P = F1V = m1w (P is power, V is speed, W is angular speed, M1 is the rotor torque provided by electric vehicles). If the electric vehicle keeps the same power P, as the tire gas decreases, it is necessary to provide a larger rotor torque M1 to overcome the resistance. As soon as the rotation moment becomes larger, the angular speed W will be reduced accordingly. slow.
TIPS: Tire without Qi will not only affect the speed, but also a very large security risk. It is found that you have to replenish qi in time!
Reference materials:
Why is it more laborious when riding a tire to ride a tire? | NO.159
by Justu
Q.E.D.Q5 at the same power, why the microwave oven is heating food, some heat up, and some heating slowly. Such as meat, chocolate, etc., it is hot in ten seconds. And water, soup, this type of heating is very slow. by sunnyxustin Answer:
Two important factors that affect heating speed are the polarity of material and comparison. Daily foods are generally non -conductors, and microwaves in microwave ovens can penetrate into the food. The essence is the microwave of electromagnetic waves, which is about 2.45GHz, which can induce the rapid rotation of polar molecules in the interchange electric field.
During the rotation process, the molecules will interact and generate heat, which is the principle of microwave heating. It can be seen that polar molecules are important conditions for food can be effectively heated. Most of the food contains water, and the chain segments of fat molecules (trigramloglcel ester) and protein, sugar, etc. composed of glycerin and fatty acids are polar. Activity generates calories. It can be seen that most foods can be heated by microwave.
However, we often say that "heating completion" often refers to the increase to a certain temperature, which involves the heat capacity of various foods, that is, the calories that need to be absorbed every 1 ° C for each increase. In order to give more meticulous and intuitive data, Xiaobian uses a variety of food components given in a paper (Reference Data 1) at different temperatures to compare the fitting formula at different temperatures.
It can be seen that the ratio of water is much higher than the protein and fat, and the ratio of the ratio of carbohydrates (that is, sugar) is the lowest. Therefore, although soup water or high water content can absorb energy from microwave radiation in the movement of water molecules, the temperature brought by the unit energy is only half of other foods. Foods such as meat, chocolates, and other foods that contain more protein, fat, and sugar can be heated faster. Especially foods with many fat content but less water content are easy to become confused when heating too fast, so pay special attention.
Reference materials:
1zhu x. Prediction of Specific Heat Capacity of Food Lipids and Foods [D]. The ohio state university, 2015. 2015.
Micro-wave oven
Revealing the working principle of the microwave oven, the reason for the high efficiency and heat and heat, this time I finally understood it!
Microwave and RF: Differences and advantages
Fat structure
by Yunkai Leaves
Q. How to correct the astigmatism with glasses? Is it possible to correctly correct it? By Anonymous Answer:
The encyclopedia introduced:
Astigmatism is a refractive incorrectness caused by the refractiveness of the eye refractiveness. The patient's eyes cannot evenly focus on the retina, which will cause vision distortion, distortion, and vagueness at any distance.
The translated into a big vernacular is that the surface of your crystal body is no longer a uniform curved surface, but a larger arc in a certain direction, a smaller arc in the other direction, just like the dwarf -fat earth, the arc of the passing line, the radian of the pass line It is inconsistent with the arc of the latitude. This will cause the object to be scattered in the meridian direction after the crystal is focused on the image point, which is inconsistent with the weft line, so your retinal can not receive a clear image in all directions at the same time. This is also called San in optical instruments.
To extremes, the lens is a lens that is completely curved in the direction of the bus and bent horizontally. Then it will only be used in the horizontal direction, and it is not imaged in the homeline direction, and it will spread away from the light. Such a point light source will be imaged as a parallel line parallel to the bus.
Then, if you want to correct the astigmatism, you must wear a lens with different arcs in different directions to correct the refractive level in different directions. The example in the figure below is to weaken the refractiveness of the horizontal direction, and retain the refractiveness in the original vertical direction.
Therefore, as long as your astigmatism is not highly high, you can correct this level of demand that meets the daily clear imaging.
Reference materials:
Astigmatism
Images Formed by Cylindrical Lens | PHYSICS FORUMS
ASTIGMatism, What is AsstigMatism?, WHO GETS ASTIGMATISM?, What HAPENS to Vision WHEN People HAVELMATISM?, What is the time.
BY Shepherd
Q.E.D.Q7 We know that white light comes from a variety of different colors, wavelengths, and frequencies. So how does the light source emit these wavelengths and frequencies? By's strange water answer:
First of all, it is necessary to clarify that different colors, wavelengths, and frequencies are essentially the same thing, or one -to -one correspondence. Now that the color is said, it is aimed at visible light, that is, the wave length is roughly in the range of 400-700nm. Because the light used in general lighting is spread in the air, the speed of light is similar to the vacuum speed
It can be seen that the wavelength is inversely proportional, which is basically one -to -one, and the wavelength corresponds to the color.
There are two types of white light lighting sources in life: incandescent lamps and white light LEDs. The principles are inconsistent. The principle of incandescent lamps is hot radiation. The filament made of tungsten wires and other materials produces heat due to the law of scorched ear under the state of power, which makes the filament constantly heated until it reaches 2000 degrees. At this time, electrons outside the nucleus will be excited to excitement, and when the transition is low, it will radiate energy in the form of electromagnetic waves, that is, glowing.
As shown in the figure above, because there are many tracks outside the atom, the beginning and end of the energy -level transition is not unique, and the transition meeting of different levels of energy (energy difference is ΔE). "Currentcolor" file = "Currentcolor" stroke-width = "0" transform = "matrix (1 0 0-1 0)">
A photon with a specific frequency is generated, where H is the Planck constant. Therefore, the diversity of ΔE creates the diversity of radiation light frequency, that is, white light is generated.
The generation of white light LED is different. The principle of light sources of LED lights is electrode light, and its physical essence is: in the PN knot composed of an excessive N -type semiconductor and PN semiconductor, when the front flow flows, the role of electronics and cavities in the electric field in the electric field The lower -direction interface movement, and the photon is released at the interface. The energy of the photon is similar to the energy corresponding to the semiconductor gap, so the corresponding frequency is more concentrated, which is a monochrome light. Different semiconductors have different light colors due to different band gaps, so there are LED light sources such as blue and red.
So how does the quasi -lust LED light source emit white light? One of the common methods is to apply fluorescent powder that can emit the coloring light on it, such as yellow light fluorescent powder on the surface of the blue LED, so that the blue and yellow light mix can form white light, called fluorescent powder conversion. Another method is to mix the light of the three primary colors of the light -the light of the red and green blue light to form a white light, which is called a multi -chip type. It seems that such a common white light really contains rich physical principles!
Reference materials:
How to make LED white?
What are the differences in the light of incandescent lights, neon lights, and energy -saving lamps? | White Light | Red Light | Filat
Baiguang LED's Luminous Principles -Zhihu.com (zhihu.com)
How does Bai Guang come out? What is LED?
LED's luminous principle
by Yunkai Leaves
Q.E.D.Q8 Theoretically, how high is the highest mountain on the earth? By Anonymous Answer:
How high the mountain is affected by many factors, the most obvious factor is gravity. The mountains must be affected by gravity on the earth. The more you delay the gravity of the upper rock, the greater the gravity of the upper part. When the gravity reaches a certain degree, the rock may be pressed into dust, and the mountain cannot be held. In addition to gravity, factors such as atmospheric weathering, plate structure, magma or lava viscosity are also related. The weathering and corrosion of the atmosphere will weather the rocks of the high -rise. The movement of the plate can form a volcanic island chain, so that the ground magma is not only erupted in the same place. Therefore, the mountains will not be piled up in the same place. The higher the magma viscosity, the greater the slope formed after the cooling out of cooling, and the easier it is to accumulate.
Now let's see how gravity is considering only, how high the mountains can theoretically reach.
If the mountains do not fall, the rock molecules on the benchmark sea level of the earth surface, the pressure from the mountains cannot exceed the limit of the rock molecule itself. The mountain cannot be maintained. This requires the rock molecular gravity energy (G) at the highest point of the mountain.
The gravity of rock molecules can be written as:
E is a small proportion of the rock material bonding energy B, which is expressed as
Among them, B is the bonding energy of rock substances. For metal and minerals, μ is generally 0.05 in order. B can be written
According to a silicon dioxide mountain body as an example, the average molecular mass of the rock molecular molecular is 60, that is, A is 60. Then comprehensive formula, calculation can be obtained, the maximum height of the mountain is about
Therefore, when we only consider gravity, the mountains on the planet seem to not exceed 20,000 meters. In addition, Mr. Niu Wenyuan also provides a theoretical height of calculating the mountain according to the rocky method. If you are interested, you can view the reference materials.
However, the above calculations are calculated in the case of only gravity. In fact, due to the reasons listed in the first paragraph, the actual height of the mountains on the earth must be less than this value. At present, the highest peak of the earth is still the peak of Mount Everest, and the height does not exceed 100,000. Meter.
Reference materials:
Why can the mountains on Mars be so high, and the highest peaks on the earth cannot exceed 9000 meters?
By Frost Bai
Q.E.D.#Voting#q q q q q
Yunkai leaves, shepherds, music Superman, Justiu, Frost White
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