# 2D Motion on an Air Table

#### Abstract

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

Yes

#### Principles Illustrated

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

#### NCEA & Science Curriculum

PHYS 2.4, PHYS 3.4

#### Instructions

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.

Note: 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

#### Safety

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