Gravitational Force Calculator

Newton's Law of Universal Gravitation

Every mass in the universe attracts every other mass with a force: F = Gm₁m₂/r²

• G = 6.674 × 10⁻¹¹ N·m²/kg² — the gravitational constant
• Force is always attractive (never repulsive)
• Follows an inverse-square law — double the distance → quarter the force
• Produces the same acceleration on both bodies (Newton's 3rd Law)

Surface Gravity

A special case: gravity at a planet's surface. F = mg where g = GM/R². For Earth: g = 9.81 m/s².

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