Unit 2A Force and Motion

motion

A change in an object’s position over time

reference point/point of reference

A place or object used to compare and detect motion.

position

The location of an object compared to a reference point.

speed

How fast an object is moving.

acceleration

A change in speed or direction of motion.

deceleration

A decrease in speed (slowing down).

direction

The path an object is moving (e.g., left, right, up, north).

constant speed

Staying the same; in motion, it means speed does not change.

force

a push or a pull on an object

unbalanced force

A force that causes a change in motion.

balanced forces

Equal forces that cancel each other and don’t cause motion to change

net force

The total force acting on an object.

inertia

The tendency of an object to resist changes in motion.

friction

A contact force that resists motion between two surfaces.

gravity

A force that pulls objects toward each other.

Newton's 1st Law of Motion

An object in motion will stay in motion and an object at rest will stay at rest UNLESS acted upon by an unbalanced force.

Newton's 2nd Law of Motion

Force will cause a change in the motion of an object. The change in motion depends on the amount of force and the mass of the object.

Newton's 3rd Law of Motion

For every action, there is an equal and opposite reaction.