What are determinants of motion?

what are the TYPES OF MOTION?

the motion occurs along or parallel to an axis

all points on the moving object travel the same distance, in the same direction with the same velocity, and at the same time

When translation occur in a curved line is called?

What this picture called?

body motion occurs around the axes within their planes of motion

When translation occur in a straight line is called?

The motion occurs in a circle around an axis

Individual points on the object move at different velocities, and the velocity of each point is related to its distance from the axis of motion  Pivot Point (Axis of Rotation)

What this picture called?

What this picture called? (A)

a plane of motion is perpendicular to the axis of motion around which it rotates

how far a force moves a body and the magnitude a body or is displaced

measured in meters or feet

positive and negative components

movement on the Z-axis (anterior-posterior axis)

movement on the Y-axis (superior-inferior or vertical axis)

measured in degrees

movement on the X-axis (medial- lateral axis)

movement on the Y-axis (superior-inferior or vertical axis)

movement on the X-axis (medial- lateral axis)

movement on the Z-axis (anterior-posterior axis)

rate at which a body or segment moves

rate at which a change in velocity occurs

translatory motion- meters or feet per second (m/s, ft/s)

rotary notion- degrees per second (o/s)

motion occurring around an axis

translatory motion- m/s per second or ft/s per second

rotary notion- o/s per second (o/s2)

it is merely force applied in an arc of motion around an axis

the state of a balanced system both forces are equal

the motion of a body or segment that occurs when force is applied

is the amount of matter contained within an object

is the force of gravity acting on the object

- a push or a pull that produces displacement

- Dimensions: Magnitude and direction

Results of force acting at a distance from point of motion (axis) (M= d x F)

Perpendicular distance from the force vector to the joint's axis of motion (Rotational forces)

Perpendicular distance from the force vector to the center of motion (Translational forces)

Measure of force (kgf)

FOUR Primary sources of force affect body movement

the resistance to movement between two objects that are in contact with each other

- it provides motion of body segments and of the entire body

- whatever the muscles must work against to produce motion

- the most prevalent force that all structures encounter

- GRAVITATIONAL FORCE is commonly referred to as "weight" of an object, body, or body segment

if a body is at rest, it will remain at rest , and if a body is in uniform motion , it will remain in motion until an outside force acts upon it

for every action force there is an equal and opposite reaction force

the (a) of a body proportionate to the magnitude of the net forces (F) acting on it and inversely proportionate to the mass (m) of the body

two dimensions of forces

is a quantity that is completely specified by its magnitude and its direction

Vector forces can be combined when______________ is applied to a body or segment.

The combination of these vectors will result in a new vector, called the?

a simple machine that consists of a rigid bar that rotates around an axis (fulcrum)

THREE ELEMENTS OF MECHANICAL LEVERS

the perpendicular distance from the axis to the line of action of the resistance

the perpendicular distance from the moving force to the axis

has its axis of rotation positioned between the opposing force

-Balance

- point of resistance application lies between the force and the axis

- Power

- point of force application located between the resistance and the axis

- Speed

the forces whose combined magnitudes and directions produce a single vector known as the resultant vector

is the division of a vector into two or more component vectors

the ratio between the length of the force arm and the length of the resistance arm

- is the theoretical point around which the mass of the object is balanced

- it is around this center that gravity acts

- line of force

- anterior to T11 and just below the xiphoid process of the sternum

- slightly anterior to S2 (55% of a person's height)

- these pulley systems may change the course of a tendon or improve a muscle's mechanical advantage by increasing its force arm distance from the joint

- the area within the points of contact of the body and any object the individual relies on for support

- the potential for a muscle to cause a torque in a particular rotation direction and plane

Which of the following types of muscle activation

the muscle lengthens during activation

a shortening of the muscle

refers to the contraction of a muscle detached from the body and lifting a load vertically against gravity

when a muscle produces force no apparent change in the joint angle

occurs when the rate of movement is constant

MUSCLE FUNTIONAL ACTIVITY

sometimes referred to as PRIME MOVERS

a muscle or a muscle group that provides the opposite anatomic action of the agonist

a muscle that contracts at the same time as the agonist

occur when two or more forces are pulling in different directions on an object, causing the object to rotate about its axis