As an object falls under the influence of gravity its speed changes in a very regular way. During every second of fall it gains a speed of 9.8 meters per second. Its acceleration is therefore 9.8 meters per second every second (or 9.8 meters per second per second or 9.8 meters per second squared.)

Bouncing Ball
Chaotic Pendulum
Falling Feather
Gravity Well
Lunar Lander
Pendulum Table
Plant Geotropism
Reaction Time
Resonant Pendulum
Stop the Drop
Strobe Fountain
Whirling Watcher

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