Force of gravity between two objects

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The discussion revolves around calculating the gravitational force between two 100 kg cars separated by 25 meters. The user is unsure if they are using the correct values in the gravitational force formula, F = G(m1m2/r^2), where G is 6.67 x 10^-11 Nm²/kg². A participant points out that using 100 kg for each car results in an extremely small force, approximately 0.0000001 N, and questions if the mass should actually be 1000 kg instead. The conversation highlights the significant decrease in gravitational force with increased distance, emphasizing the weak nature of gravity at such separations. Understanding these calculations is crucial for grasping the concept of gravitational interactions.
pinkcarnations
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hi i am stuck and don't know what to do next or if i am even on the right path. could someone help me please! :cry:

my question is what is the force of gravity between two 100kg cars separated by a distance of 25m on an interstate highway?
I started out like this:


fg=Gm1m2+6.67 x 10-11Nm2 x (1000kg) (1000kg)
r2 kg2 (25m)2



G=6.67 x 10-11 Nm2
kg2



then i don't know what to do or if this is even close






thanks to anyone with the time to help.
 
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Just plug in the CORRECT values in the formula for F:
F=\frac{Gm_{1}m_{2}}{r^{2}},G=6.67*10^{-11}\frac{Nm^{2}}{kg^{2}},r=25m,m_{1}=m_{2}=100kg

Query:Check the value of the mass for each car; are you sure it is 100kg, rather than 1000kg?
 
It gives me an extremely small result. Something like 0.0000001 N. It makes sense btw.
 
Last edited:
Would you expect anything else?
 
arildno said:
Would you expect anything else?

No because gravity weaks considerably with the distance (action at a distance).
 
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