Gravitational acceleration affects falling objects equally
DOI:
https://doi.org/10.64804/j4w7r827Keywords:
gravity, mass, speed, kinematics, Galileo, Aristotle, free fall, acceleration, baseball, kickball, R, dplyr, ggplot2Abstract
This experiment examines two hypotheses about the motion of falling objects: Aristotle’s idea that heavier objects fall faster than lighter ones, and Galileo’s idea that objects fall at a constant acceleration when air resistance is negligible. Five drop tests were conducted in which we released a kickball (m=0.210 kg) and a baseball (m=0.144 kg) from a height of 5 m to obtain the times it took for each object to fall a distance of 5 m. The measurements allowed us to estimate the acceleration experienced by each. Baseballs fell in 0.84+/-0.08 s, while kickballs fell in 0.84+/-0.087 s; the resulting accelerations were 14.7+/-2.8 m/s2 and 14.5+/-2.4 m/s2, respectively. Accelerations were approximately equal, regardless of mass; and differences between time to fall and between acceleration were not statistically significant, thus supporting Galileo’s hypothesis that objects fall at a constant acceleration when air resistance is negligible.
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Data are available at https://github.com/devangel77b/427snagrani-lab1/
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