關於Brownian morion的問題。

2008-07-17 3:19 am

大家應該有聽說過Brownian motion，粒子在其它粒子的碰撞下會作不規則的運動。可是根據統計物理學，如果碰撞那粒子的其它粒子作不同隨意運動(random motion)的碰撞，那麼在大量的碰撞下，那粒子所受到的淨力應是零，故它應是靜止不動。

可是實際情況是，那粒子作不規則運動。而這現象，一直困擾著科學家二百多年。直至1905年愛因斯坦才用數學去證明那粒子是作不規則運動。

請問各位，可以詳細說明其證明的內容嗎?

回答 (1)

[匿名]

2008-07-26 6:33 am

✔ 最佳答案

About 150 years ago a botanist, Robert Brown, observed pollen grains moving in a random way under his microscope. You can see the same effect with smoke today. We call it Brownian Motion.

Brown thought the movement of the grains may be explained by the fact that the pollen was alive! But in fact it was some years before it was explained that the movement was due to collisions between the pollen and millions of smaller (and therefore invisible) gas atoms.

The pollen was small enough to be knocked sideways when more air particles collided with one side of it than with the other. This was evidence of the continuous movement of gas atoms. Gas atoms have Ek.

參考: http://www.s-cool.co.uk/topic_quicklearn.asp?loc=ql&topic_id=49&quicklearn_id=2&subject_id=68&ebt=451&ebn=&ebs=&ebl=&elc=13

👍 0 👎 0