Weight and Gravitational Force Weight is related to mass, but they are not the same.

Weight Weight is a measure of the gravitational force on an object. An object’s weight can change with the location of the object in the universe. Weight is expressed in the SI unit of force, the newton (N). U.S unit is pounds (lbs.) A spring scale is used to measure weight.

MASS Mass is a measure of the amount of matter in an object. An object’s mass does not change when gravitational force changes. Usually expressed in kilograms (kg) or grams (g). A balance is used to measure mass.

Homework - Key questions 1) How does the gravitational force between objects that have small masses compare to the gravitational force between large objects? 2) What happens to the gravitational force between objects as the distance between them increases? 3) If you went to the Moon, why would your weight change but your mass would stay the same?

Answers 1) Objects that have less mass have less gravitational pull then larger objects, because as mass increases the gravitational pull also increases. 2) As the distance between objects increases the gravitational pull decreases. 3) Your weight would change on the moon because there is less gravity there and weight in a measure of the gravitational pull. Mass stays the same because the matter in the object stay the same.