8th grade vocab

3. an object at rest stays at rest until acted upon by a force
4. occurs when something speeds up, slows down, or change direction
5. the acceleration of an object is equal to the net force acting on the object divided by the objects mass
6. a measure of how hard it is to stop a moving object
7. forces acting on an object that combine and form a net force of zero
9. forces acting on an object that combine and form a net force that is not zero
11. an attractive force that exist between all objects that have mass
14. a push or a pull on an object by another object that is touching it
16. a push or a pull on an object
18. any motion in which an object is moving along a curved path
19. a force that one object applies to another object without touching it

1. a principle stating that the total momentum of a group of objects stays the same unless outside forces act on the objects
2. for every action there is an equal and opposite reaction
8. the gravitational force exerted on an object
10. the combination of all the forces acting on an object
12. in circular motion, a force that acts perpendicular to the direction of motion, toward the center of the curve
13. the tendency of an object to resist a change in movement
15. the forces two objects apply to each other
17. a force that resist the motion of two surfaces that are touching