Foreces and Newton´s first Law (vocabulary # 1)

Force:a push or pull exerted by one object on another

Friction:a force that opposes the motion of an object in  contact with the surface

drag force:a force that oppose the motion of and object through a liquid or gas.

 

 gravity:a force of attraction that exist between all object with mas

 

net force:the combined effect  of all the forces acting on an object

balanced force: forces that cancel each other out when acting together on a single object

unbalanced force: forces that do not cancel each other out when acting together on a single object

inertia:the tendency of an object to oppose a change in motion

momentum: the mass of an object multiplied by its velocity