Gravitation Concepts and Newton's Discovery

Gravitation

• Gravitation is a universal force, acting between any two objects in the universe
• It wasn't just discovered between earth and objects on it but extends to the entire universe
• Sir Isaac Newton discovered gravitation by observing an apple falling from a tree
• The apple fell vertically downwards, not at an angle, leading Newton to the idea of earth's attraction
• The force of attraction is towards the earth's center
• The direction from the apple to the earth's center is the vertical direction

Concept of Gravitational Force

• The gravitational force between the Earth and the apple is directed towards the Earth's center (vertically).
• The gravitational force between the Earth and the moon is directed towards the Earth's center
• The force of attraction is independent of the height
• The Force could affect objects much farther from the Earth
• Examples include the moon and other planets.

Newton's Observation

• Newton observed that the apple fell vertically downwards.
• He wondered why apples fall vertically and not horizontally.
• Newton concluded that Earth's attraction towards its center causes the apple to fall vertically.