Potential Energy and gravitation

AI Thread Summary
The discussion centers on the role of the gravitational constant (G) in equations related to gravitational force and potential energy. The equation F=G m1m2/R^2 describes the force between two masses, while U=mgh represents gravitational potential energy. The negative sign in U=-Gxm1xM2/r+K indicates that gravitational potential energy decreases as two masses come closer together. The gravitational acceleration formula g=-GM/r^2xr_hat also uses -G to signify the attractive nature of gravity. Overall, G serves as a conversion factor, and its negative sign is a convention reflecting the attractive force of gravity.
shounakbhatta
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Hello,

Can someone please explain me:

F=G m1xm2/R^2

In potential energy U=mgh

Generally it is also written that:

U=-Gxm1xM2/r+K. How -G comes into play?

Also Newton's above law of Gravitation in vector form is written as:

F_12=-Gm1m2/r12^2 r12

Here also how -G comes into play?

Coming to Gravitation acceleration:
If one of the masses is larger than the other, gravitational field is defines as:

g=-GM/r^2xr_hat

How again -G comes into play?

If somebody can explain in a step by step method....


Thanks,

-- Shounak
 
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Upper-case G is the universal gravitational constant. It is basically just a conversion factor. It is negative by convention.
 
Hello,

What is the conversion factor?

Does that mean the equation for G and -G are the same?

-- Shounak
 

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