The key difference between gravitation and gravity is that Gravitation is the force of attraction between any two masses, while gravity specifically denotes the force that pulls objects towards Earth.
What is Gravitation?
Newton’s law of gravitation states that any particle of matter in the universe attracts any other particle with a force that is directly proportional to the product of their masses and inversely proportional to the square of the distance between them.
This attraction force, denoted as F, can be expressed as F = G(m1m2)/R^2, where G is the gravitational constant—a universal constant whose value depends on the system of units used. Newton formulated this law in 1687, using it to elucidate the observed movements of planets and moons, which Johannes Kepler had earlier described mathematically in the early 17th century.
What Is Gravity?
Gravity, in mechanics, is the fundamental force of attraction that acts universally between all matter. While it is the weakest known force in nature, it does not influence the internal characteristics of everyday matter. However, due to its vast reach and universal effect, gravity governs the paths of celestial bodies in the solar system and beyond, as well as the structure and evolution of stars, galaxies, and the entire universe.
On Earth, every object experiences a gravitational force, known as weight, which is proportional to its mass and is exerted by Earth’s mass. Gravity’s intensity is measured by the acceleration it imparts to objects in free fall. At the Earth’s surface, this acceleration is approximately 9.8 meters (32 feet) per second squared.
Therefore, each second an object is in free fall, its speed increases by approximately 9.8 meters per second. On the Moon’s surface, the acceleration due to gravity for a freely falling object is about 1.6 meters per second squared.
Gravitation vs Gravity
The primary difference between gravitation and gravity is that:
| Aspect | Gravitation | Gravity |
|---|---|---|
| Definition | Force of attraction between any two masses. | Force that pulls objects towards Earth. |
| Scope | Applies universally. | Specifically applies to Earth. |
| Origin | Derived from Newton’s law of universal gravitation. | Resultant force due to Earth’s gravitational field. |
| Applicability | Applies to any two masses in the universe. | Applies to objects near Earth’s surface. |
| Mathematical Law | Described by Newton’s law of gravitation. | Described by Newton’s law of gravitation. |