Newton’s Law of Universal Gravitation

Asra AlSuwaidani Michael De Rosa

Caitlyn Doran

Before The Discovery of Gravity

The ancients believed that the stars, the planets, and the Moon move in divine circles, free from any impelling forces. And as far the ancients were concerned, this circular motion required no explanation.

Before The Discovery of Gravity

But there were gravitational theories before Newton’s arrived.

Aristotle believed that heavier objects accelerated faster.

Before The Discovery of Gravity

In the late 16th century and early 17th century, Galileo began work on gravitational theory.

Galileo’s experiments of dropping balls from the Tower of Pisa showed that gravity accelerates all objects at the same rate.

Galileo’s theory pretty much set up the work for Newton’s to create the theory of gravity.

The Law of Universal Gravitation

Newton explained that “Gravity” is the force of attraction between the earth and any other object.

Later on, he proposed that gravity was only a specific case of gravitation.

“Every mass in the universe attracts every other mass” this is the main idea of Newton’s Law of Gravitation

The Law of Universal Gravitation

Newton reached his final aspect of The Universal Gravitation Law (Every mass in the universe attracts every other mass ) after studying the three laws of motions.

The Three Laws of Motion:

First Law: Objects move in a straight line with a consistent speed, or don’t move, unless a force acts to change their speed of direction.

Second Law: (Force= Mass * Accelerations ); The accelerations produced by forces are in proportion to the mass of an object.

Third Law: Every action produced by

a force has an equal and opposite reaction.

The Three Laws of Motion:

“Every particle in the universe exerts a force on every other particle along the line joining their centers. The magnitude of the force is directly proportional to the product of the masses of the two particles, and inversely proportional to the square of the distances between them. (Newton, 1687)

The Law of Universal Gravitation

In Mathematical terms:

M1: The mass of object AM2: The mass of object B R: The distance between A and BF: the gravitation force between A and B G: the universal gravitation constant 6.67 *10 ^(-11)

After The Discovery of Gravity

After Newton discovered that the reason objects fall to the ground is because of gravity, the way people think has not been the same. Gravity is one of the important elements in the physics world, let alone the world we live in today.

After The Discovery of Gravity

Without gravity, simple every day things we do would never be possible. We could never just sit at the kitchen table for dinner or in a lecture of 150 people.

(Things would be floating around the room!!)

After The Discovery of Gravity

Without the discovery of gravity, Edison would have never been able to create the light bulb, or John Glenn would have never been able to walk on the moon.

After The Discovery of Gravity

Newton’s discovery has changed the way people think forever.

If it wasn’t for his discovery, We would still believe that the smoke rises because it is going to its natural state in the air or that an apple hits a person on the head because it is merely returning to its state on the ground.

This important discovery has been the building blocks for almost all of the important discoveries in the science community today.

Recourses:

Gravity and Gravitation. The history of gravity. Retrieved from http://science.jrank.org/pages/3129/Gravity-Gravitation-history-gravity.html

Hewitt, P. (2009). Conceptual Physics. Boston, MA: Pearson Education.

Suite101. Newton’s law of motion. Retrieved from http://physics-history.suite101.com/article.cfm/newtons_laws_of_motion

Suite101. Newton’s law of gravitation. Retrieved from http://physics-history.suite101.com/article.cfm/newtons_law_of_gravitation

Think Quest. Newton’s law of universal gravitation. Retrieved from http://library.thinkquest.org/C007571/english/advance/background1.htm