Brownian motion

High school (ages 12+)
Science & Technology

Name:

Date:

Step 1 · Read the article

Open the article and read it at the level above. Then answer the questions below in your own words.

https://smallwhale.org/articles/brownian-motion

Write what each word means, using the article.

Do not copy the article. Write two things you learned, the way you would explain them to a friend.

Answers below are taken from the article’s stored facts, so they match what the student read.

1. What is the scientific classification?Stochastic process, specifically a random walk
2. What is the first observation?Robert Brown, 1827, while studying pollen in water
3. Why do pollen grains wiggle in water?Pollen grains wiggle in water because the tiny water molecules are always moving and collide with the pollen. These collisions push the pollen in different directions, making it zig‑zag.
4. How did scientists prove that atoms exist using Brownian motion?Scientists used Brownian motion to show that atoms are real. Einstein wrote equations that linked the particles’ wiggling to the motion of atoms, and Jean Perrin measured the motion and found it matched Einstein’s predictions.

Brownian motion: The random, erratic movement of microscopic particles suspended in a fluid medium.
Stochastic process: A mathematical model describing a sequence of random variables over time.
Thermal equilibrium: A state where a system and its surroundings have the same temperature, with no net energy flow.
Wiener process: A specific type of stochastic process that mathematically models Brownian motion.