Gravity and Satellite Equations

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The discussion focuses on compiling modified equations related to gravity and satellites for exam preparation. Key equations mentioned include the relationship between mass, period, and gravitational force, specifically using centripetal force equations. Participants suggest that rather than memorizing equations, it's more beneficial to derive them from fundamental principles, as this aids long-term understanding. However, one user prefers to have a ready list of equations for easier reference during the exam. The conversation emphasizes the importance of understanding the derivation process while also acknowledging the need for practical exam strategies.
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This isn't quite a question, I've got an exam coming up and I'm compiling a notes sheet I've found gravity and satellites troubling, I know most of the general equations, but I was wondering if I could get a set of equations which have been modified to find each measure...

So far I've got Mass? =
(4(pie)^2)*(R^3)
___________
(T^2) * G
Period?
T = 2(pie)R
_____
v
T^2 = (4(pie)^2) * R^3
____________
G Constant * Mass

Has anyone got anymore modifications that I can put on my notes sheet?
 
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You're trying to memorize all modifications of the same equation? Why don't you just practice combining and solving them for the variable you're interested in? Memorizing will make you forget shortly after your exam, deriving them yourself from the base principles that is F_{centripital}=F_{gravity} will last a life time!
 
Nah, we are aloud to bring in a A4 sheet of notes into our exam, and since I'm not very good at deriving equations, I just wanted someone to give me a basic list of equations which would make it easier for me in my exam.
 
Well in that case perhaps we should derive a few. For an orbiting satellite the centripetal force is provided by gravity, therefore F_{centripital}=F_{gravity}. F_{centripital}=m \omega^2 r=m v^2/r and \omega= 2 \pi f=2 \pi /T =v/r.F_{gravity}=GmM/r^2.

Therefore the equations to solve are:
m\omega^2 r=\frac{GmM}{r^2}

and

m \frac{v^2}{r}=\frac{GmM}{r^2}

So far you have solved them for T and M, correctly. If you want all possible combinations you will have to solve them for v,f,r, \omega as well. Try to start with v.
 
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