Unraveling the vertical motion of Dipterocarpus alatus seed using Tracker

TL;DR

This study analytically and experimentally investigates the vertical motion of Dipterocarpus alatus seeds, deriving equations of motion, confirming predictions with data, and highlighting implications for seed dispersal and STEM education.

Contribution

The paper develops an exact analytical model for seed vertical motion considering velocity-dependent drag, validated by experiments, and discusses educational applications.

Findings

Predicted seed trajectories match experimental data.

Terminal velocity of seeds is accurately determined.

Seed dispersal is primarily straight downward.

Abstract

We perform analytical and experimental investigation of the vertical motion of Dipterocarpus alatus seed, locally called Yang-na in Thailand. In this work, we assume the drag forces exerting on the Yang-na seeds depend only on the velocity. We derive equations of motion (EoMs) to physically parametrize the vertical motion of the seed and analytically solve to obtain the exact solutions. Interestingly, we observe that our predicted solutions are in agreement with the experimental data. More precisely, the entire trajectory of the falling seed of Yang-na can be described by our predicted solutions. We also determine terminal velocity of the seeds. Remarkably, this work reasonably proves that seed dispersal characteristics of Yang-na is inherently straight downward. Finally, we believe that our achievement will be valuable to the large community of STEM/STEAM education to promote an understanding in the topic integrating mathematics, physics, biology, art and technology. Our framework constitutes learning model to improve the ability of creative thinking, analytical thinking and problem solving skills on the concept of forces and motion applicable from high school to college levels.