Gravitation is the universal force of attraction between objects, responsible for the motion of celestial bodies and varying weights on Earth. #### Medium Summary This section explores the concept of gravitation as the force that causes the motion of objects, detailing Isaac Newton's universal law of gravitation, the effects of gravity on different masses, and the conditions under which objects float in liquids. It emphasizes the universality of the law across celestial and terrestrial realms. #### Detailed Summary # Gravitation Gravitation refers to the force that attracts two bodies towards each other. It is foundational for understanding the motions of celestial bodies and how objects behave under the influence of gravity on Earth. ## Key Topics: - **Definition of Force**: Force is essential for altering the speed or direction of an object's motion. - **Observations of Gravity**: Objects fall to Earth when dropped, and celestial bodies like planets and moons exhibit orbits due to gravitational forces. - **Isaac Newton's Contribution**: Newton recognized that a universal force, termed gravitational force, governs the interactions between all objects. - **Universal Law of Gravitation**: The force of attraction between two objects is proportional to their masses and inversely proportional to the square of the distance between them. - **Variation of Weight**: Weight can differ based on location due to the variation in gravitational pull. - **Floating Objects**: The conditions under which objects float depend on the buoyant force acting on them relative to their weight. - **Weak Nature of Gravitation**: This force is relatively weak unless large masses are involved, which is why it predominantly influences astronomical bodies. Overall, gravitation plays a critical role in the universe, affecting both terrestrial phenomena and the movement of celestial objects.