Discover the Source of Earth's Centripetal Force: Is It Gravity?

AI Thread Summary
The centripetal force that keeps Earth in orbit around the sun is indeed gravity. This force acts towards the sun, providing the necessary pull for the orbit. While some debate the definition of gravity, it is mathematically defined by Newton's law of universal gravitation. The discussion clarifies that gravity can be considered a force when applying the correct formula. Ultimately, gravity is confirmed as the source of Earth's centripetal force.
UrbanXrisis
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Earth goes around the sun. The centripetal force always acts towards the sun. What is the source of this force? Is it gravity?
 
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Gravity is the centripetal force.
 
Gravity isn't a force is it? Gravity isn't defined in Newtons.
 
UrbanXrisis said:
Gravity isn't a force is it? Gravity isn't defined in Newtons.

it is

F(grav) = (G*m1*m2)/(r^2)

if you're using vectors you tack on a unit vector to give it direction from the center of mass from one object to the other (and vice versa)
 
you're right, I was thinking about g (acceleration due to gravity), not gravity itself.
 

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