PIRA Classification: 1J11.13
Description: A tower consists of three boards and light aluminum supports. The supports are set up such that the tower can be sheared. Below the second board hangs a plumb bob, indicating the center of mass. When the tower is sheared, the plumb bob will move toward an edge of the bottom board. When the plumb bob passes the edge, the tower will tip.
Special Instructions: Shear the tower in the direction indicated by the arrow.
Setup time: 1 minute
Safety Issues: None