Originally posted by strNick
....At least, run a game based on Source engine (Half-Life 2 or Counter-Strike Source, for example) and set sv_gravity 100 (default value is 600) so
it will be like on the Moon, then jump. Do the same with sv_gravity 384 (64%). Compare the results (and don't forget to compare them with the Apollo
film)....
We are talking about the gravity of the moon acting upon an object
on or nearits surface. This is the
Gravity Due To
Acceleration we are talking about. We aren't talking about the gravitational attraction between the Earth and the Moon.
Why should we consider the distance between the Earth and Moon when trying to figure out the force of gravity on an object or body near the surface of
the Moon? That makes no sense. We don't take the Sun's distance to the Earth into consideration when we figure out the
Acceleration due to
Gravity on the Earth, do we?? When we talk about the gravity on Mars (which is a little more that 1/3 Earth) we don't care how far Mars is from
the Earth --
-- so why do you care now how far the Earth is to the Moon?
Here's how you calculate the force of gravity on a body (Accelaration due to Gravity) on the surface of the Moon and Earth.
Acceleration due to gravity (Agrav) = GxM / R^2
Calculate the acceleration due to gravity on the Moon (Agrav[moon]):
- The Gravitational Constant (G) is 6.67 x 10^-11 meters^3 per kg^-1 per second^-2
- Moon's mass (M) is 7.35 × 10^22 kg.
- The Moon’s radius (R) is 1.74 × 10^6 meters
Agrav [moon] = GxM / R^2
= (6.67 × 10^-11) x (7.35 × 10^22) / (1.74 × 10^6)^2
Acceleration due to Gravity [moon] = 1.62 meters/sec^2
Calculate the acceleration due to gravity on the Earth (Agrav[earth]):
- The Gravitational Constant (G) is 6.67 x 10^-11 meters^3 per kg^-1 per second^-2
- Earth's mass (M) is 5.97 × 10^24 kg.
- Earth’s radius (R) is 6.37 × 10^6 meters
Agrav [earth] = GxM / R^2
= (6.67 × 10^-11) x (5.97 × 10^24) / (6.37 × 10^6)^2
Acceleration due to Gravity [earth] = 9.8 meters/sec^2
Therefore, the difference in Acceleration due to gravity of the Moon and Earth =:
Agrav[moon] / Agrav[earth] =
1.62 / 9.81 =
0.16503 or 1/6
therefore the gravity acting on a body on or near the
surface of the Moon is 1/6 the gravity acting on a body on or near the surface of the
Earth. The distance of the earth to the Moon is not practically relevant in this calculation
EDIT TO ADD:
Here's a link to a picture of the calculations that might be easier to read (it's hard to show math on this board):
files.abovetopsecret.com...
[edit on 7/3/2009 by Soylent Green Is People]