Question

In an experiment to demonstrate Brownian motion, smoke was placed in an air cell and observed under a microscope, Smoke particles were observed to move randomly in the cell.

1. Explain the observation 
2. Give a reason for those of smoke in this experiment 
3. What would be the most likely observation if the temperature in the smoke cell was raised?

Answer 1

1. Fast moving air molecules move continuously and randomly and collide with the smoke particles.
2. Larger particles may not be moved much by the fast moving air particles.
3. Increase in air temperature would increase the speed of air molecules and hence the number of collisions would be more.