Mass vs. Weight & Inertia
- 1. What is Gravity? A force of attraction between objects due to their masses. This attraction causes objects to pull on other objects.
- 2. How does mass & distance affect the gravitational pull between objects? Large mass & close in distance = Large gravitational pull/force Close in distance, but small mass = Small gravitational pull/force Large mass, but large distance = Small gravitational force
- 3. What is Weight? The amount of gravitational force exerted on an object. The sponge & brick are the same size (volume), but the brick has a much larger mass The Earth’s gravity will pull on the brick more = MORE WEIGHT for the brick Sponge Brick Example:
- 4. Why do people often confuse the terms mass & weight? On Earth, mass & weight remain constant so people use the words as if they mean the same thing *Weight DEPENDS on Mass – They are not the same thing!
- 5. Mass is………. A measure of the amount of matter in an object Always constant no matter where the object is in the universe Measured with a triple beam balance Expressed in grams (g)
- 6. Weight is………. A measure of the gravitational force on an object Varies depending upon where the object is in relation to the Earth (or any other large body in the universe) Measured with a spring scale Expressed Newtons (N)
- 7. FINAL SUMMARY MASS STAYS THE SAME! WEIGHT CAN CHANGE!
- 8. What is Inertia? The tendency of all objects to resist any change in motion. An object at rest will stay at rest unless a force causes it to move An object in motion will stay in motion unless a force causes it to stop.
- 9. How does mass affect inertia? More mass = more inertia *HARDER to start or stop an object Less mass = Less inertia *Easier to start or stop an object