Talk:Equations for a falling body

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Are there any equations already worked out to show the changes in height, velocity, and accelecteration with respect to the change in gravitional acceleration due to the proximity to a the massive body.

[edit] Possibly change equations?

I don't like how it uses Earth's acceleration due to gravity. Should the equations be changed to these?

Distance d travelled by an object falling for time t:	$\ d=\frac{Gmt^2}{2r^2}$
Time t taken for an object to fall distance d:	$\ t =\ \sqrt {\frac{2dr^2}{Gm}}$
Instantaneous velocity v_i of a falling object after elapsed time t:	$\ v_i = \frac{Gmt}{r^2}$
Instantaneous velocity v_i of a falling object that has travelled distance d:	$\ v_i = \sqrt {\frac{2Gmd}{r^2}}\$
Average velocity v_a of an object that has been falling for time t (averaged over time):	$\ v_a =\frac{Gmt}{2r^2}$
Average velocity v_a of a falling object that has travelled distance d (averaged over time):	$\ v_a =\frac{ \sqrt {2Gmd}}{2r} \$

with G being the gravitational constant and r being the distance from the center of the main body

Tell me if I made a mistake in these, I'm not used to working with Wikipedia's math coding. Yanah 20:40, 17 October 2006 (UTC)

Well, g is more convenient than GM/r for Earth uses. I would favor the equations in terms of g, with the qualifier that for other planets and for significantly different radii than Earth's, g must be replaced with GM/r where the M and r are chosen appropriately as other than Earth-surface normal. S B H arris 22:39, 17 October 2006 (UTC)

- I agree with you, these equations are way too dependant. I also think it would be better for first-time readers if we clarify m/s² as (m/s)². -HuBmaN!!!! 06:16, 19 November 2006 (UTC)

- - Huh? If you're talking about acceleration or gee, the units are m/s² and certainly not (m/s)² = m²/s². S B H arris 06:42, 19 November 2006 (UTC)

If you are trying to perform a calculation like landing an object on the Moon both g and r change with time. The integral formula may be better. Andrew Swallow 06:31, 20 September 2007 (UTC)