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Coherence between Brain Cortical Function and Neurocognitive Performance during Changed Gravity Conditions
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The illusion of weightlessness

Sarah Wakes1, Joanne Caudwell

  • 1Department of Design Studies, University of Otago, Dunedin, New Zealand. sarah@design.otago.ac.nz

International Journal of Injury Control and Safety Promotion
|October 9, 2009
PubMed

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When an object is dropped, it accelerates toward the center of the Earth. If the net external force on the object is its weight, it is said to be in free fall; that is, the only force acting on the object is gravity. Galileo was instrumental in showing that, in the absence of air resistance, all objects fall with the same acceleration g. However, when objects on the Earth fall downward, they are never truly in free fall, because there is always some upward resistance force from the air acting...
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