Catatan Darell Jeremia SItompul chat dengan AI Jumat, 24 Februari 2023
Darell:
Why in a manometer, with one side is open to the air and the other have a litttle air pushig them, one of the water height is bigger than the other one?
AI:
In a manometer, the difference in height of the water columns on either side of the U-tube is caused by the difference in pressure between the two sides. When one side of the manometer is open to the air and the other side has a little air pushing on it, the pressure on the side with the air is slightly greater than the pressure on the open side, resulting in a higher water level on that side.
The pressure difference between the two sides is due to the weight of the air above each side. In the open side of the manometer, the pressure is equal to atmospheric pressure because it is exposed to the air. However, on the side with the little air pushing on it, there is a slightly higher pressure due to the weight of the air in the tube and the weight of the atmosphere above it.
This pressure difference causes the water to move up the tube on the side with the higher pressure, resulting in a higher water level on that side. The difference in height of the water columns can be used to measure the pressure difference between the two sides of the manometer.
Darell:
Do we need to calculate the velocity of the "little air pushing" on the other side?
AI:
In the context of a simple manometer, there is no need to calculate the velocity of the "little air pushing" on the other side. The pressure difference between the two sides of the manometer is primarily due to the weight of the air, not its velocity.
In a manometer, the height difference between the two columns of liquid is directly proportional to the pressure difference between the two sides. This pressure difference is a result of the weight of the air in the tube and the weight of the atmosphere above it. Therefore, the pressure difference can be calculated based on the height difference of the liquid columns and the density of the liquid being used.
It's worth noting that in some more complex systems, the velocity of a fluid or gas may be an important factor in determining pressure differences. In these cases, more sophisticated calculations and measurements may be required. However, for a simple manometer with one side open to the air and the other with a "little air pushing," velocity is not a significant factor.
Darell:
When you said that the air pushing creates a pressure to the liquid, does the air that pushes the other side is spread evenly?
AI:
In the case of a manometer where one side is open to the air and the other side has a "little air pushing," the air pressure on the liquid in the manometer is distributed evenly across the surface of the liquid.
The pressure exerted by the air on the liquid is a result of the weight of the air in the column above the liquid. This weight is distributed uniformly across the surface of the liquid, so the pressure is also evenly distributed.
It's important to note that in some cases, such as if the air column is moving, there may be variations in pressure across the surface of the liquid. However, in a static manometer with a small amount of air pressure on one side, the pressure is generally evenly distributed across the liquid surface.
Dari percakapan singkat ini, saya memahami bahwa dalam manometer bentuk U udara yang mendorong air menyebabkan tekanan kecil di salah satu sisi tabung. Kecepatan dari udara tersebut tidak terlalu berpengaruh karena informasi yang diperlukan adalah tekanan yang disebabkan oleh dorongan udara tersebut.
Pak DAI menjelaskan bahwa dalam tekanan, ada yang namanya tekanan statis dan tekanann dinamik. Dalam tekanan statis, tekanan dianggap tersebar secara merata (seperti dalam pembelajaran kali ini tekanannya dianggap merata).
Tekanan dinamik digunakan untuk mengukur laju aliran udara. Contoh alat pengukur tekanan dinamik adalah tabung pitot (pitot tube).
