Question

Почему бороуновское движение в жидкости и газе является хаотическим и почему оно происходит тем заметнее, чем мельче размеры частиц

Answer 1

Поскольку молекулы, ударяя друг друга, постоянно меняют траектории своего движения. Мы можем только предположить, какова будет траектория движения молекулы после удара, но наверняка мы этого не знаем. То есть они движутся хаотично

Answer 2

Brownian Motion in Liquids and Gases

Brownian motion refers to the random movement of particles suspended in a fluid or gas. This phenomenon was first observed by the botanist Robert Brown in 1827 when he noticed the erratic motion of pollen grains suspended in water. Brownian motion is caused by the constant collisions between the particles and the molecules of the surrounding medium.

The chaotic nature of Brownian motion: Brownian motion is considered to be chaotic because the movement of the particles is unpredictable and random. The particles move in a zigzag pattern, constantly changing direction and speed. This randomness arises from the cumulative effect of countless collisions with the surrounding molecules, which are constantly moving and colliding with each other.

The effect of particle size: The visibility of Brownian motion becomes more pronounced as the size of the particles decreases. This is because smaller particles experience more frequent collisions with the surrounding molecules due to their larger surface area-to-volume ratio. As a result, their motion becomes more erratic and noticeable.

The random motion of particles in Brownian motion can be explained by the kinetic theory of gases. According to this theory, the motion of gas molecules is governed by their kinetic energy. The particles in Brownian motion exhibit similar behavior, constantly changing their direction and speed due to the transfer of kinetic energy during collisions.

In summary, Brownian motion in liquids and gases is chaotic and unpredictable due to the cumulative effect of countless collisions between the suspended particles and the surrounding molecules. The motion becomes more noticeable as the size of the particles decreases, as they experience more frequent collisions.