Forces cause objects to speed up, slow down, or change direction through direct contact or through interaction at a distance
A force is a push or a pull that can cause an object to start moving, stop moving, change speed or change direction.
A force has both a size and a direction.
Some forces are contact forces such as pushing, pulling and friction and only work when the object is touched, and some are noncontact forces such as magnetism and gravity which can move an object without touching it.
Humans employ simple machines and compound machines to apply pushes or pulls (forces) that make things move
Six simple machines help humans do work.
Simple machines can be combined to make compound machines.
