2D Motion on an Air Table


Frame from the video showing the path of the puck.
Frame from the video showing the
path of the puck.

Puck moves in 2D, colliding with wire boundaries. Analysed with Tracker or VideoPoint. Extensive data analysis is included.



Principles Illustrated

Motion in 2 D, data analysis, position, velocity, and acceleration.

NCEA & Science Curriculum

PHYS 2.4, PHYS 3.4


The camera is mounted well above the table, at a height of about three meters. The camera is connected to a computer with FireWire running Tracker or VideoPoint or similar software. We use Tracker extensively and recommend it. The puck should move moderately fast or there will be large errors in the velocity and acceleration due to small changes in position. The numerical derivatives used to calculate velocity and acceleration distort the data somewhat.

xvt-SmallNote: When using Tracker or VideoPoint delete the first data point. The time for this data point is incorrectly assigned the value t = 0 seconds.

The distance from the edge of the table to the mark is 1 meter, as shown in this scale photo. This can be used to scale the movie in Tracker or VideoPoint.

Definitely need two blowers.

Note that the collisions are not very elastic.

Example Data

Data and Commentary


Individual teachers are responsible for safety in their own classes. Even familiar demonstrations should be practised and safety-checked by individual teachers before they are used in a classroom.

Related Resources

Collisions on an air table

Teaching Resources

Would you like to contribute lesson suggestions? Contact us.


PIRA 1N40.20


This teaching resource was developed with support from

The MacDiarmid Institute
Faculty of Science, Victoria University of Wellington
School of Chemical and Physical Sciences, Victoria University of Wellington


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