Unit 3 Vocabulary

The rate at which the velocity of an object changes

• average acceleration

• acceleration

• Displacement

• Free-fall acceleration

The change in an object's velocity during a measurable time interval divided by that specific time interval; measured in m/s²

• Average velocity

• Average acceleration

• Instantaneous acceleration

• Centripetal acceleration

The motion of an object when air resistance is negligible and the motion can be considered due to the force of gravity alone.

• Free-fall accleration

• Free-fall

• Average acceleration

• Instantaneous acceleration

The change in an object's velocity at a specific instant in time.

• Average accleration

• Instantaneous accleration

• Negative accleration

• Equilibrium

A graph that has velocity plotted on the vertical axis and time plotted on the horizontal axis; its slope is the acceleration of the object whose motion is described by the graph.

• Positon-time graph

• Distance-time graph

• Acceleration-time graph

• Velocity-time graph

The acceleration of an object due only to the effect of gravity.

• Free fall

• Free-fall acceleration

• Terminal velocity

• Gravitational acceleration

Newton's first law of motion

• States that an object at rest will remain at rest and a moving object will continue moving in a straight line with constant speed, if and only if the net force acting on an object is zero.

• States that the acceleration of an object is proportional to the net force and inversely proportional to the mass of the object being accelerated.

• States that the angular acceleration of an object is directly proportional to the net torque on it and inversely proportional to its moment of inertia.

• States that all forces come in pairs and that the two forces in a pair act on different objects, are equal in strength, and are opposite in direction.

Newton's second law of motion

• States that an object at rest will remain at rest and a moving object will continue moving in a straight line with constant speed, if and only if the net force acting on an object is zero.

• States that the acceleration of an object is proportional to the net force and inversely proportional to the mass of the object being accelerated.

• States that the angular acceleration of an object is directly proportional to the net torque on it and inversely proportional to its moment of inertia.

• States that all forces come in pairs and that the two forces in a pair act on different objects, are equal in strength, and are opposite in direction.

Newton's third law of motion

• States that an object at rest will remain at rest and a moving object will continue moving in a straight line with constant speed, if and only if the net force acting on an object is zero.

• States that the acceleration of an object is proportional to the net force and inversely proportional to the mass of the object being accelerated.

• States that the angular acceleration of an object is directly proportional to the net torque on it and inversely proportional to its moment of inertia.

• States that all forces come in pairs and that the two forces in a pair act on different objects, are equal in strength, and are opposite in direction.

Free-body diagram

• A physical model that represents the forces acting on a system

• A series of images that represent the motion of an object taken at regular time intervals

• A simplified version of a motion diagram in which the moving object is replaced by a series of single points

• A coordinate system from which motion is viewed