Gravitational Potential Energy formula confusion! (1 Viewer)

lemon1

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Hello guys, i'm getting really stressed out about this. Could someone please explain what i have to do here! I have no-one to help me especially that my teach is, well, lets not go there..

I see three formulas here:

Ep = -G mMe/r where M = the mass of the earth

F = G m1m2/r^2

Ep = G m1m2/r


My question is, what is going on, why is there 3 formulas here, what is the difference between them, and which do i use and when.

Sorry for the stupid question, i'm currently spamming my head with other subjects i am starting to ware out -_-

thankyou! <3 :)
 

_deloso

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Ep = -G mMe/r where M = the mass of the earth
The gravitational potential energy between a mass orbiting the Earth
-This is a negative value because Ep is zero when a mass is not in the Earth's gravitational Field. This means that the mass needs to be at an infinite distance from Earth but infinity cannot be achieved.

F = G m1m2/r^2
This is not a gravitational potential energy formula. This is Newton's Law of Universal Gravitation which explains the force between two different masses. You'll learn this later on in the syllabus.


Ep = G m1m2/r
The Gravitational Potential Energy formula between two different masses.
 

lemon1

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Ep = -G mMe/r where M = the mass of the earth
The gravitational potential energy between a mass orbiting the Earth
-This is a negative value because Ep is zero when a mass is not in the Earth's gravitational Field. This means that the mass needs to be at an infinite distance from Earth but infinity cannot be achieved.

F = G m1m2/r^2
This is not a gravitational potential energy formula. This is Newton's Law of Universal Gravitation which explains the force between two different masses. You'll learn this later on in the syllabus.


Ep = G m1m2/r
The Gravitational Potential Energy formula between two different masses.
THANKYOU so very much ! ! :) <3
 

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