Motion

• Brownian motion is useful because it helped indirectly to confirm that atoms exist
• The dust particles are not always moving downwards but are moving in all directions
• Dust particles


  Very small particles supported by a fluid (gas)
• The gas particles are too small to be seen directly, but the larger dust particles can be observed moving randomly
• The random movement of the dust particles is caused by collisions with the gas particles
• The random movement of the dust particles is similar to a game of snooker, where the small gas particles collide with the larger observable dust particles
• Brownian motion


  The random movement of small particles suspended in a fluid (liquid or gas) caused by their collision with the fast-moving molecules in the fluid
• Brownian motion was first observed by scientist Robert Brown, who noticed pollen grains suspended in water under a microscope appeared to be jiggling randomly