Summary
- Free fall occurs whenever an object is acted upon by gravity alone.
- An object in free fall experiences an acceleration due to gravity.
- The acceleration due to gravity…
- is a natural phenomenon
- is represented by the symbol g (italic)
- varies with location
- is effectively 9.8 m/s2 over the entire surface of the Earth
- is independent of mass
- always points down (in a sense, it's the definition of down)
- The standard acceleration due to gravity or standard gravity…
- is a natural unit of acceleration
- is represented by the symbol g (roman)
- is very nearly equal to the acceleration due to gravity in Paris, France
- is equal to 9.80665 m/s2 by definition, but can be rounded to 9.8 m/s2 or even 10 m/s2 for convenience
- is sometimes used to quantify frame of reference acceleration, informally and incorrectly called "g force"
- does not have a direction (in fact, no unit has a direction)
