Newton's Law of Universal Gravitation Calculator
Calculate gravitational attraction force (Newtons and lbf), free-fall acceleration, and planetary orbital pull using Newton's law F = G(m1·m2)/r².
Calculated Results
Frequently Asked Questions
What is Newton's Universal Law of Gravitation?
Formulated by Sir Isaac Newton in 1687, the law states that every particle of matter attracts every other particle with a force directly proportional to the product of their masses and inversely proportional to the square of the distance between their centers: F = G(m1·m2)/r^2.
What is the Gravitational Constant G?
G is an empirical physical constant with a value of approximately 6.67430 × 10^-11 N·m^2/kg^2. It was first measured experimentally by Henry Cavendish in 1798 using a torsion balance.
Why does gravitational force obey the inverse-square law?
Because gravitational field lines radiate outward uniformly in all three spatial dimensions. As the radius r doubles, the surface area of the spherical sphere increases by fourfold (4πr^2), diluting the force intensity by 1/r^2.
How does gravitational force differ from gravitational acceleration?
Gravitational force (F) is measured in Newtons and depends on both masses. Gravitational acceleration (g = G·M/r^2) is the rate of free-fall acceleration experienced by any object near a planet, independent of the falling object's mass.