Brownian Motion

Question 1

How was Brownian motion first seen?

Answer 1

Robert Brown noticed tiny particles of pollen suspended in water moved with a zigzag, random motion.

Question 2

How can Brownian motion be seen in the lab?

Answer 2

1) Put some smoke in a brightly illuminated glass jar and observe the particles using a microscope.
2) The smoke particles appear as bright specks moving haphazardly from side to side, and up and down.

Question 3

What is the cause for Brownian motion?

Answer 3

The randomly moving air particles were hitting the smoke particles unevenly, causing this motions.

Question 4

What is Brownian motion evidence for?

Answer 4

Existence of atoms or molecules in the air.