Newton’s universal law of gravitation

Definition

Newton’s Universal Law of Gravitation states that every particle in the universe 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. This law is mathematically expressed as $F = G \frac{m_1 m_2}{r^2}$, where $F$ is the gravitational force, $G$ is the gravitational constant, $m_1$ and $m_2$ are the masses, and $r$ is the distance between their centers.

5 Must Know Facts For Your Next Test

1. The value of the gravitational constant $G$ is approximately $6.67430 \times 10^{-11} \text{N}(\text{m}/\text{kg})^2$.
2. Gravitational force acts along the line joining the centers of two masses.
3. The gravitational force decreases with the square of the distance; if you double the distance between two masses, the force becomes one-fourth.
4. Newton’s Universal Law of Gravitation applies universally, from subatomic particles to astronomical bodies.
5. This law explains both terrestrial gravity (e.g., objects falling on Earth) and celestial gravity (e.g., orbits of planets).

Review Questions

Related terms

Gravitational Constant ($G$): $G$ is a universal constant used in Newton's Universal Law of Gravitation, approximately equal to $6.67430 \times 10^{-11} \text{N}(\text{m}/\text{kg})^2$.

Inverse Square Law:

A principle stating that a specified physical quantity or intensity decreases proportionally to the square of the distance from its source.

Uniform Circular Motion:

Motion in a circular path at a constant speed; an object undergoing uniform circular motion experiences centripetal acceleration directed towards the center.