A push or a pull.
Equal in size or magnitude AND Opposite in
Unequal in size/magnitude, OR In SAME direction, AND Causes a CHANGE in the object's motion.
The combination of all the forces that act on an object
The force of attraction between ALL objects.
Center seeking - pulls toward the center of rotation (circle).
The tendency of an object to resist change in motion.
A force that opposes the motion of an object.
Force that must be overcome to start an object moving.
Solid surfaces slide over each other.
Object rolls over a surface.
Objects moving through a fluid - water, air, etc.
Materials that reduce friction.
The frictional force that opposes the downward motion of objects falling through the atmosphere.
The speed in a given direction
the velocity reached when the upward force of air resistance becomes equal to the downward pull of gravity and forces becomes balanced so it doesn't go any faster than it is.
The pull of gravity on the mass of an object
The pull of objects to a magnet
The push on an object, such as a kite
Gravity pulling down on water
The expanding and contracting of your muscle to move your body
The force produced by any bent or stretched object
Empty space where there is no air resistance
Objects falling in a vacuum