## elementary physics

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Posts: 567
Joined: 2004.07
Post: #1
my dad and I started to make a game, hopefully we'll finish it tonight, made after Space Wars. We used the equation for acceleration toward the sun as a = G / d, where a is acceleration, g is gravity, and d is distance squared. Pretty simple. is there anyway to calculate the gravity other than manually, preferably using masses?

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Post: #2

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Posts: 567
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Post: #3
Thanks you. is F approximately equal to acceleration, or would I have to calculate another variable for that?

It's not magic, it's Ruby.
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Post: #4
Force = Mass x Acceleration

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kingofsquirrels
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Post: #5
Just to elaborate:

F = (G)(m1)(m2) / r^2
Where G is the gravitational constant, m1 is the mass of the smaller object (space ship), m2 is the mass of the planet, and r is the distance between the two objects.

F = (m1)(a) for the smaller object

Therefore:
(m1)(a) = G(m1)(m2) / r^2
a = G(m2) / r^2

The acceleration depends only on the mass of the planet, not at all on the mass of the space ship.
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Posts: 567
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Post: #6
Thanks! That really helps!

It's not magic, it's Ruby.

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