What is the meaning of air humidity? How is it calculated?

What is the meaning of air humidity? How is it calculated?

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What is the concept of air humidity?
What does the dehumidifier mean by 96%?

At a certain temperature, the maximum moisture content in the air is considered as 100
Now the largest percentage of water in the air is the current air humidity
For example, people feel comfortable is 40% - 60%

What is the meaning of 100% air humidity? What is the concept of 100% humidity?

Under certain conditions of temperature and pressure, the amount of water vapor contained in unit volume of air has a certain limit. When the water vapor content does not reach this limit, it is called unsaturated air; when the water vapor content just reaches this limit, it is called saturated air, When water and water vapor reach the equilibrium state, evaporation stops. The air in this state is called saturated air, also called saturated wet air. At this time, the air humidity is 100%

What is the density of water______ The physical meaning of it is______ ．

The density of water is 1.0 × 103kg / m3, which means that the mass of water with a volume of 1m3 is 1.0 × 103kg

What is the density of water kg / M? What is its physical meaning
"What" is the horizontal line

It's the three sides of kg / m
It reads "kilogram per cubic meter"
Represents the mass of a substance per unit volume

What is the density of water and what is its physical meaning

The density of water is 1000kg / m3, the physical meaning is: the mass of water per cubic meter is 1000kg

The density of water is 1000kg / m3. What is the physical meaning of this?
I wrote "the ratio of mass to volume of water" on the test paper. The result is wrong. What is the correct answer?

The mass of one cubic meter of water is 1000 kg
Believe me, I've done it a thousand times

What is the answer to question 24 on page 25 of Newton's first law?

1: There is no external force, static uniform linear direction size 2-4: ACD
5: The speed friction is smooth, small, long, small and slow
6: Air resistance of two pieces of paper landing at the same time
7：2 134 2314 24he 25!

Scientific observation can be observed by comparative methods, such as observation and comparison______ 、________ 、_______ And temperature, etc

Color, size, shape

Xiaomin, a student of a certain school, has a strong interest in biology. She is good at observation and diligent in thinking. Some creative ideas of biological exploration often appear in her mind. One day, when she was visiting the peach garden in Surabaya, she looked at the red peach blossoms on the branches and suddenly wondered: if you give the peach blossom pear pollen, can it still bear fruit? With the support of the teacher, she and her classmates carried out the exploration together. The steps are as follows: ① select 20 peach blossoms in the orchard and divide them into two groups A and B equally. ② remove the stamens of these peach blossoms and cover them with breathable bags. ③ collect some peach blossom pollen and pear blossom pollen respectively. ④ apply peach blossom pollen on the stigma of group A and pear blossom pollen on group B According to their design, please complete the following questions: (1) what are the variables in this experiment______ (2) steps 3 and 4 complete the process of plant reproduction______ In addition, it must be completed before the fruit and seed are formed______ (3) the experimental results show that group A produces peaches, so what is the significance of designing group B______ ．

(1) In group A and B, the other conditions are the same because peach pollen is coated on the stigma of group A and pear pollen is coated on the stigma of group B. therefore, the variable of this experiment is pollen (or pollen type)