Description: This demo shows the linear nature of a laser beam by releasing chalk dust or fog in the lasers path.
- laser on stand
- black board eraser (with chalk dust) or aerosol fog
- Turn on the laser.
- Turn off the lights.
- Clap the eraser or spray the fog in the path of the laser
- Note that you can now see the laser beam because the laser light is scattered off the particles and enters your eyes.
- When finished, turn off the laser.
Do not stare at the laser beam. Do not point the laser at students.
Note: This picture is time elapsed. In person, the beam will not be as bright.