Why do we need to stand outside the yellow line to wait for the subway when we wait for the subway? Because when the local railway expressway passes by you, the air flow rate between you and the subway has increased and the pressure has decreased, while the air flow rate behind you has not changed, so you will feel a thrust behind you, pushing you into the track, which is an extremely dangerous behavior! So what is the principle?
Physicist Daniel Bernoulli proposed in 1726 Bernoulli Principle : Fluid Mechanics Before establishing the theoretical equation of continuous medium , the basic principle adopted in fluid mechanics was its essence to conserve the mechanical energy of the fluid. That is: kinetic energy + gravity potential energy + pressure potential energy = constant. Its most famous inference is that when high flow is , the flow rate is high and the pressure is small. has an experiment on "Will the table tennis ball fall" in in 号号号号号号号号号号号号号号号号号号号号号号号号号号号号号号号号号号号号号号号号号号号号号号号号号号号号号号号号号号号号号号号号号号号号号号号号号号号号号号号号号号号号号号号号号号号号号号号号号号号号号号号号号号号号号号号号号号号号号号号号号号号号号号号号号号号号号号号号号号号号号号号号号号号号号号号号号号号号号号号号号号�
In order to understand the Bernoulli principle more intuitively, we can do a simple experiment, take two pieces of paper and blow air between them. At this time, the paper did not flutter as we expected, but instead fit together. This is also because the air flow rate in the middle becomes larger and the pressure becomes smaller. The air pressure on the outside of the paper is strong and the two pieces of paper are "pressed" together!
Historically, the collision event between the "Olympic" and the "Haoke" is a very typical Bernoulli principle. When the two ships sail forward in parallel, the water in the middle of the two ships flows faster than the water on the outside, and the pressure on the inside of the middle of the water on the inside of the two ships is smaller than the pressure on the outside of the two ships. So, under the pressure of the water outside, the two ships gradually approached and finally collided. The "Haoke" is light and runs faster under the push of this big hand. Therefore, the "Haoke" hits the "Olympic". Now this phenomenon is also called " ship sucking phenomenon " on the sea.
Whether it is a subway, high-speed rail, or bus, we must treat everyone equally, keep a safe distance when waiting for the bus, and don’t cause tragedy just by one step!
