Activity

Air cannon (with dry ice)

Summary
Make a fast-moving vortex of gas emerge from a box with a hole. Adding dry ice to the box makes the vortex visible.
Science content
Physics: Motion and Forces, Newton’s Laws, Gravity (K, 2, 6)
Lessons activity is in
Materials
  • cardboard box
  • scissors and tape
  • plastic bag
  • dry ice and gloves to handle
  • warm water
  • container to hold the dry ice that will fit in the box
    Procedure

    Construct the cannon:
    Cut a hole on one side of the box (works best if this is about half the diameter of the box).
    Cut part of the other side of the box out, and tape a plastic bag over it, so it is a little flexible.
    Add a handle to the plastic with tape, so that it can be pulled back and forth.

    Add the container of warm water and dry ice to the box.
    Once the box fills with dry ice gas, draw back the plastic then move it forwards quickly.
    A vortex of gas should emerge from the hole (best seen against a dark background).

    Scaled down, individuals can each make their own vortex.

    Notes

    http://www.waynesthisandthat.com/airblasters.html

    With no dry ice in the box, a vortex of air is still made, which will travel to move light objects on the other side of the room.

    Grades taught
    Gr 4