## Inflation and Tilt Vectors (Grades 4-6)

Balloons are excellent tools to demonstrate the relationship
between inflation and tilt vectors. Tilt vectors show the magnitude and
direction of tilt. The greater the amount of inflation, the greater the
amount of tilt and the longer the tilt vector. Balloons, markers,
rulers, protractors, and a simple map of Kilauea Caldera are needed.
Students can work in pairs or small groups. Inflate a balloon
three-quarters full. Outline a simple map of Kilauea Caldera on the top
of the balloon. Draw three arrows on the outside of the caldera,
pointing away from the rim. Measure and record the length and slope
angle (tilt) of each arrow. Inflate the balloon as large as possible.
Remeasure the length of each arrow and the tilt. The length and tilt of
each arrow increased. Compare the balloon model to Kilauea Volcano. As
the volume of magma in the reservoir increases, the volcano inflates, and
tilt vectors grow and point away from the caldera.