Universal gravitation - radius?

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SUMMARY

The discussion centers on the application of Newton's law of universal gravitation, specifically the formula F = G * (m1*m2)/(r^2). The gravitational constant G is defined as 6.6673x10^-11 N*m²/kg², with m1 representing the mass of the Earth (6x10²⁴ kg) and m2 representing the mass of the Moon (7.4x10²² kg). The average distance between the Earth and the Moon is 3.9x10^8 m, and the correct interpretation of r² in the formula is to use the full distance (3.9x10^8 m) squared, not half of that distance.

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Mirole
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Using F = G * (m1*m2)/(r2)

We know that

G = 6.6673x10-11 N*m2/kg2
m1(earth) = 6x1024 kg
m2(moon) = 7.4x1022 kg
the Earth and moon are an average of 3.9x108m apart

would r2 be [3.9x108]2 or [3.9x108 / 2]2?

-Thanks!
 
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Why would you divide the distance in half?
 
Here we are using radius...!
So, the first one is correct.

Here the distance between the two bodies mean the distances from their centres.
So, definitely, they are mentioning the radius
 

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