Gravity: A Force of Attraction
Chapter 5 Section 4 Lydia and Keifer
The Effects of Gravity on Matter
All matter has mass! Gravity is a result of mass. Compared to all other objects the Earth has the biggest mass (so a HUGE mass). Earth's gravitational force pulls everything toward the center of the earth. Because of the big force books, tables, and chairs in the room stay in place, and all dropped objects fall to the ground (Earth) rather than moving together or toward you.
Newton and Study of Gravity
Unbalanced forces are needed to change the movement of objects. Newton summarized his ideas about gravity in a law that is now known as the law of gravitation.
The Law of Universal Gravitation
Part 1: Gravitational force increases as mass increases
Part 2: Gravitational force decreases as distance increases
Weight as a Measure of Gravitational Force
Weight is related to mass but they are not the same. Mass is the amount of matter in an object and weight is a measure of the gravitational force on an object.
Weight
A measure of the gravitational force on an object.
Mass
A measure of the amount of matter in an object
Gravity
A force of attraction between objects due to their masses