Expert Answers
ishpiro eNotes educator| Certified Educator

The Universal Law of Gravitation states that any two bodies are attracted to each other by the force of gravity. This force can be calculated using the following formula:

`F_(g) = (G*m_1*m_2)/r^2`

Here, G is the universal gravity constant, equal to 6.67*10^(-11) N*m^2/kg^2, m_1 and m_2 are the masses of the bodies, and r is the distance between the bodies.` <br> `

The main features of this law are:

  • the force is always attractive, which means all matter in the universe is always being pulled together.
  • it is proportional to the mass, which means the heavier the objects, the stronger the force pulling them together.
  • it is inversely proportional to the square of the distance between the objects. This means that the further away the objects are from each other,  the weaker the gravity force acting between them. Besides that, the fact that the distance is squared (as opposed to just distance, or distance cubed) explains. among other things, why the planets follow elliptical orbits around the Sun and why a ball thrown horizontally follows a parabolic path towards the ground.
loves2learn | Student

Newton’s Law of Universal Gravitation states that “every object in the universe attracts every other object with a force directed along the line of centers for the two objects that is proportional to the product of their masses and inversely proportional to the square of the separation between the two objects”

This is converted into the following formula:

`F_(g)=G((m1*m2)/(r^(2))) `


Fg= force of gravity

G= universal gravity constant (6.64 x 10^-11 (Nm^2)/kg^2)

m1 and m2= the masses of the two objects you are comparing

r= distance between the objects.


Access hundreds of thousands of answers with a free trial.

Start Free Trial
Ask a Question