Chapter 5

2. equilibrium/the condition if which all forces acting on a system are balanced as indicated by the systems lack of acceleration
4. acceleration/when objects accelerate at a constant rate
7. that determines how much force is required to change their motion
9. force/force exerted by all matter on other matter; the weakest of all fundamental forces
10. force/the single unbalanced force acting on a system that is the sum of all forces acting on the system. if they are balanced, then the net force is zero
14. force that opposes the movement of objects past each other
16. force/a force exerted on a system by something in its surroundings
17. forces/act only when one system touches another
18. usually described as a push or pull on a system
19. velocity/with zero zero acceleration the objects velocity is constant for the remainder of its fall

1. change of a systems momentum directly proportional to the force exerted and the time interval over which the force is applied.
3. force/force exerted by a supporting surface on an object resting on it
5. description of such a spatial region
6. continue moving indefinitely unless they are affected by some external influence
8. resistance in the form of friction
11. fall/objects that fall due to gravity alone with no other forces acting on them
12. forces/forces whose pushes and pulls cancel each other out
13. momentum/momentum of a rotating object
14. force/the force exerted on objects by a field
15. for force