Biomechanics-Linear Kinematics: Describing Objects in Linear Mo

Defined by all points on a body moving in circles about the same fixed central line or axis/all points on the body move through same angle

Angular Motion (Rotation)

Characteristics of kinematics include?

Position, Distance,Displacement,Speed,and Velocity, Acceleration

Occurs when an object speeds up, slows down, starts, stops, or changes directions?

Acceleration

is the distance traveled by the time it took to get there

Average speed

is the displacement of an object divided by time it took for that displacement

Average velocity

Sign of velocity and sign of acceleration the same:?

Body is speeding up

Position is Often described using the ? System

Cartesian Coordinate

What (describes object in space using three numbers in three dimensions often along a x, y, and z axis.

Cartesian Coordinate system

What kind of motion - similar to rectilinear motion except that there is a constant change of the direction of the motion.

Curvilinear Motion (translation

is a type of straight- line distance in a specific direction

Displacement

is defined as the measure of the length of the path followed by the object whose motion is being described from its starting position to its ending position; does not take into account direction

Distance traveled

Classifying motion as linear, angular, or general motion makes the mechanical analysis of movements ?

Easier

Most common form of motion you will see

General motion

Most examples of human movement are

General motion

This is a combination of Linear and Angular Motion

General motion

What motion ? Trunk often moves as a result of the angular motions of the legs and arms

General motion

example of angular motion

Gymnast rotating around the high bar

Does Direction of motion does indicate the direction of the acceleration?

It does not / no

What kind of kinematics? -Concerned with the description of linear motion -More specifically it is concerned with speed, distance, and direction of an object

Linear Kinematics

is the straight-line distance from starting point to finish,

Linear displacement

Kinematics is the branch of dynamics concerned with the description of ?

Motion

Speed and Velocity is Both measure rate of

Motion

Described as location in space

Position

Motion Is Defined as the process of a change in

Position

What ? Use a fixed reference point to serve as origin 1 dimension: starting line, finish line 2 dimensions: goal line, sideline, (0,0), Cartesian coordinate system 3 dimensions: ball on tennis court from baseline, from sideline, how high

Position

Two types of Uniform Acceleration:

Projectile Horizontal

-An object in the air acted on only by forces of gravity and air resistance -Consider vertical and horizontal kinematics separately.

Projectile Motion

Two types of Linear Motion to remember: .

Rectilinear Motion Curvilinear Motion

What kind of motion - all points on a body move in straight line so that there is no change in direction, orientation, or distance.

Rectilinear Motion(translation)

Must have ? and ? present in order for motion to occur

Space and time

- rate of motion

Speed

separating general motion the linear and angular components of a motion makes it easier True or false

True

Velocity is the rate of change of displacement, whereas speed is the rate of change of distance.

Velocity

rate of motion in a specific direction; has a magnitude and a direction associated with it

Velocity

What is the rate of change of velocity.

acceleration

Linear motion Examples include:

an ice skater gliding across the ice,

Sign of velocity and sign of acceleration the opposite: ?

body is slowing down

Horizontal - uniform acceleration

constant horizontal motion in a straight line

Linear motion Occurs when all points on a body move the same ?

distance, direction,time.

uniform acceleration

external force acting on an object is constant and unchanging

When Speeding up or starting: acceleration is going in ?

in the direction of motion

When Slowing down or stopping: acceleration is going in ?

in the opposite direction of motion

Three types of motion

linear, angular, general

Motion may be classified as

linear, angular, or a combination of the two (general motion).

Examples of general motion :

running, walking, biking

Rate of motion at an instant in time Time duration very ? Change in position very ? (interval of a race)

short & short

Projectile - uniform acceleration

the only force acting on an object is gravity

represents the length of the path followed from start to finish.

whereas linear distance traveled