Gravity Calculator - Gravitational Force

This physics calculator helps you calculate gravitational force between two masses using Newton's law of universal gravitation. Gravity is one of the four fundamental forces of nature.

Gravitational Force Definition

• Gravitational Force: Force of attraction between masses
• Formula: F = G(m₁m₂)/r² (Newton's law of universal gravitation)
• Always Attractive: Gravity always pulls objects together
• Inverse Square: Force decreases with distance squared

Gravitational Force Formula

• F = G(m₁m₂)/r² - Newton's law of universal gravitation
• G: Gravitational constant (6.67430×10⁻¹¹ N⋅m²/kg²)
• m₁, m₂: Masses of the two objects (kg)
• r: Distance between centers of mass (m)
• F: Gravitational force (N)

Applications

• Astronomy: Planetary motion and orbital mechanics
• Space Science: Satellite orbits and space missions
• Geophysics: Earth's gravitational field
• Engineering: Tidal forces and structural design
• Physics: Fundamental force studies
• Education: Classical mechanics and gravity

Important Notes

• Gravitational force is always attractive
• Force is proportional to product of masses
• Force decreases with distance squared
• Gravitational constant is very small
• Gravity is the weakest fundamental force

Gravitational Field

• Field Strength: g = GM/r² (N/kg)
• Earth's Surface: g = 9.81 N/kg
• Moon's Surface: g = 1.62 N/kg
• Mars' Surface: g = 3.71 N/kg
• Jupiter's Surface: g = 24.79 N/kg

Gravitational Potential Energy

• Formula: U = -G(m₁m₂)/r
• Negative: Indicates attractive force
• Zero Reference: At infinite separation
• Conservation: Total energy is conserved

Gravitational Examples

• Earth-Moon: ~2×10²⁰ N (384,000 km apart)
• Earth-Sun: ~3.5×10²² N (150 million km apart)
• Two People: ~10⁻⁷ N (1 m apart)
• Two Cars: ~10⁻⁶ N (1 m apart)

Gravitational Constant

• Value: G = 6.67430×10⁻¹¹ N⋅m²/kg²
• Units: N⋅m²/kg² (force × distance² ÷ mass²)
• Precision: Known to 6 significant figures
• Measurement: Cavendish experiment

Gravitational Effects

• Tides: Moon and Sun's gravitational pull
• Orbits: Planets around Sun, satellites around Earth
• Weight: Force of gravity on objects
• Time Dilation: Gravity affects time (relativity)