
Chapter 1
The great fall: gravity versus air
Chapter 2
Terminal velocity: the speed limit of falling
Chapter 3
Catching the wind: the art of the parachute
Chapter 4
Slicing the sky: cheating drag on the ground
YOUR GOAL
Master of The invisible wall of air
Ch 1 · The great fall: gravity versus air
artiteacher Gravity and Air Resistance
Without the air to slow the feather's flight, They hit the ground together, heavy and light.

artiteacher Air behaves like a liquid, pushing back against anything moving through it.

artiteacher Astronaut David Scott proved Galileo's gravity theory on the airless Moon.

BETA
artiteacher Drag and drop objects through different atmospheres to learn how air resistance affects falling speed.
Fun Fact
Moon gravity: Astronauts on the Moon dropped a hammer and feather in 1971, and they hit the ground at the exact same moment due to the lack of air.
Glossary
vacuum (noun)
A space entirely devoid of matter. In 1971, Commander David Scott dropped a hammer and feather on the Moon to demonstrate this concept.
A space entirely devoid of matter. In 1971, Commander David Scott dropped a hammer and feather on the Moon to demonstrate this concept.
Quiz
What is the scientific term for the friction force exerted by air on a moving object?
artiteacher Galileo Galilei challenges ancient Greek theories about how objects fall.
Quiz
Which Apollo mission featured an astronaut dropping a hammer and a feather on the Moon?
