Final Exam Flashcards
Summation of forces KINETIC LINK PRINCIPLE
- summation of forces from most proximal link to most distal link to generate force and velocity at distal link
ex. Crack the whip
- person at end flies off from
- greater velocity
- centrifugal forces
ANGULAR KINEMATICS
.vt=wr
TORQUE
FORCE x MOMENT ARM.
NEWTONS ROTARY LAWS (Rotary Inertia)
- an object will remain rotating or still unless acted upon by an external torques
ex. Earth spinning, bike tire, Frisbee
MOMENT OF INERTIA
ARMS OUT YOU WILL INCREASE YOUR INERTIA AND VICE VERSA.
DISTRIBUTION OF MASS AROUND AN AXIS THAT YOU ARE ROTATING AROUND, I=MR^2
METHODS OF GENERATING TWIST 3 OF THEM
- Zero Gravity Twist
- Action/Reaction Twist
- Rotation into Twist
CENTRIPETAL FORCES
PULLS IN (is a force that makes a body follow a curved path)
CENTRIFUGAL FORCE
PILLS OUT (is the apparent force that draws a rotating body away from the center of rotation. It is caused by the inertia of the body as the body’s path is continually redirected.)
CENTER OF GRAVITY AND STABILITY
- -segmental alignment -less stable because curvature of spine
- kyphosis
- scoliosis
- lordosis
STABILITY AND GAIT
.
STANDING POSTURE (curvature of spine)
SCOLIOSIS
MUSCLE IMBALANCES
CHEST TOO DEVELOPED- BACK PROBLEMS. “KYPHOSIS”
“LORDOSIS” - TIGHT HIP FLEXORS
“ROTATOR CUFF” - ANTERIOR GREATER THEN POST…
BACK PAIN
DIAGNOSTIC TOOL TO HELP YOU IDENTIFY THE ORIGIN OF PAIN. (muscle imbalances)
ERGONOMICS
- study of work
-designing the work place to fit the person
-started in WW2 with airplane cockpit design
-wanted consistent design
Purpose of ergonomics in workplace
-decrease risk of injury
-enhance productivity and efficiency
-improve quality of work life
Benefits of desk
-sit or stand
-can adjust to different height people
INSTRUMENTATION
KA VIDEO,
SMOOTHING,
FILM 30 FRAMES,-SOFTWARE IS 60 FRAMES
GAIT ANALYSIS
WALKING(MORE STABLE): DOUBLE SUPPORT, SINGLE SUPPORT
RUNNING: SINGLE SUPPORT(AIRBORNE)
ICE SKATING VIDEOS
SKATER 1: TRIPLE IN AIR, ARMS OUT THEN BRING EM IN,NOT GET BODY PARTS IN CLOSE ENOUGH, JUMP HIGHER.
SKATER 2: TRIPLE AXEL, (ACTION/RXN TWIST)PUSH ONE DIRECTION, NEED ANGULAR MOMENTUM, ANTICIPATE COMING OUT TOO SOON
UPPER EXTREMITY INJURIES
SCOLIOSIS: HOLD SOMETHING HEAVY IN ONE ARM.
ROTATOR CUFF MECHANICS
Mechanism-supraspinato and biceps tendon go through subacromial space, can get impared and lead to pain and inflammation
- do exercises to strengthen posterior muscles - rhomboids, posterior deltoids - rhomboids pull down scapula - make more room in subacromial space
LOWER EXTREMITY MECHANICS
GAIN ANALYSIS AND
-PRONATION
-SUPINATION
Two ways to measure leg length difference
-ASIS to medial malleolus-laying down
-greater trochanter to lateral malleolus- sitting
ROTARY AND STABILIZING FORCES OF MUSCLE
.
NEWTONS ROTARY LAWS (Torque=I x delta)
Torque=moment of inertia x angular speed
I=mr2 + m2r2 + m3 r2…each segment of a body has a moment of inertia
-each body segments center of mass times distance from axis squared has an effect on rotary
-if segments closer to axis easier to rotate than if farther away
-ex. Easier to swing bat that you choke up on because its closer to axis so you need less torque
NEWTONS ROTARY LAWS (ANGULAR MOMENTUM)
Due to conservation of angular momentum, if one segment rotates one direction another segment rotates in the opposite direction
- pull arms in once spinning and you will go faster - spinning on a board, legs go one way and arms go the other for force - I1W2=I2W2 - I= moment of inertia - W=angular velocity
NEWTONS ROTARY LAWS ( NAMES)
- ROTARY ROTATION
- Torque=I x delta)
- ANGULAR MOMENTUM
