Motion Vocab Flashcards
Motion
The act or process of changing place or position with respect to some reference object
Force relative to motion
Force must be great enough to overcome the objects inertia, or resistance to motion
Force relative to résistance
Determines if the object will move or stay put
Types of motion
Translatory or linear
Rotary or angular
Translatory Movement
An object is translated as a whole from one location to another
Rectilinear
Body is acted on by gravity or an external force
Straight - line progression
All points move at the same distance at the same speed
Curvilinear
Curved Translatory movement
All points do NOT move the same distance at same speed
General motion
Forward and backward rolls on ground
Rotary motion
Twirling on ice skates
Levers, wheels and axels
Object acting as a radius moves about a fixed point
Linear motion
Translation of the body such that its orientation in space does not change
Monitor a single or series of points
Curvilinear Translatory motion
In diving and jumping
Reciprocating motion
Swinging on a swing
Circular motion
Object moves along the circumference of a circle, a curved path of constant radius
An unbalanced force acts on the object to keep it in a circle
If the force stops acting on the object, it will move in a linear path tangent to the direction of movement when released
Angular motion
Descriptive of motion of the entire radius
General motion is a combination of what two types of motions?
Rotary and translatory
Center of mass
The point about which the mass of the object is balanced
Can be outside the body
Represents point where the total effect of gravity (weight) acts on the object
Factors that determine motion
Freely movable
Where force is applied in reference to its center of gravity
Factors Modifying Motion (External)
Friction
Air resistance
Water resistance
Factors modifying motion (internal)
Friction in joints
Tension of antagonists
Anomalies of bone and joint structure
Atmospheric pressure
Interfering soft tissues
