It is possible that many have seen online some video of tricks and tips among which we discovered that we have been serving brick milk a lifetime.
It turns out that the right way to serve milk It is with the brick's mouth up and not down, as our intuition asks us to do. And it seems that the logical thing seems to put the mouth as close as possible to the glass so as not to get out, but there is a scientific explanation to do it the other way around.
Why is it better to serve milk with your mouth up?
In the video on these lines we have summarized lA scientific explanation of why it is better to serve milk with your mouth up, but let's try to tell it a little more in detail.
It is something that has to do with the fact that the gases (of which the air we breathe is made up) always move from areas with more pressure to areas with less pressure. This is, for example, the reason why the air comes out of a flat tire (inside there is more pressure than outside) or that, for example, it "wrinkles" when descending that bottle of water that we carried on the plane (a great height there is less pressure than on land).
When we serve the milk with the brik's mouth at the bottom, what happens is that the milk occupies the entire width of the mouth when leaving, not letting the air enter. As the milk comes out, a small air bag is created at very low pressure inside the container.
That difference in pressure between the outside air (that of the room) and the air inside brik, propel the outside air into and equalize the pressure (It is a hobby that gases have).
In doing so, it cuts off the milk flow (partially or totally), and once the pressure is equalized, the milk comes out again, causing the dreaded gush that can eventually cause it to end up splashing.
And why with the face up does this not happen?
When the mouth is at the top, this does not happen, and the milk comes out smoothly, without tripping. Why?
Basically because, while we serve it, the milk does not completely block the mouth of the brik, allowing air to flow freely between the inside and outside of the container, keeping the pressure balanced.
So that later they say that physics is useless.