Motion and Forces Vocabulary

4. coherent, typically large body of matter with no definite shape.
5. the acceleration of an object is directly proportional to the net force acting on it and inversely proportional to its mass
8. the force exerted by air on an object in motion, also known as drag
11. he force that opposes the motion of an object moving through a fluid (a liquid or a gas)
13. the force that resists the relative motion between two surfaces that are at rest with respect to each other
15. the SI unit of force
16. that for every action, there is an equal and opposite reaction
17. a body's relative mass or the quantity of matter contained by it
19. unequal forces acting on an object that do not cancel each other out, resulting in a non-zero net force
20. the total momentum of an isolated system remains constant over time

1. the total force acting on an object, found by calculating the vector sum of all individual forces
2. two or more equal forces acting on an object in opposite directions, resulting in a net force of zero and no change in the object's motion
3. the force that opposes the motion of a round or curved object, like a ball or wheel, as it rolls across a surface
6. the resistance that one surface or object encounters when moving over another.
7. states that an object at rest will stay at rest, and an object in motion will stay in motion with the same speed and in the same direction, unless acted upon by an unbalanced external force
9. a property of matter by which it continues in its existing state of rest or uniform motion in a straight line, unless that state is changed by an external force
10. the force that opposes the relative motion of two surfaces in contact as one slides over the other
12. the acceleration of an object resulting from the force of gravity, which causes it to speed up as it falls
14. downward movement under the force of gravity only
18. the quantity of motion of a moving body, measured as a product of its mass and velocity.