Unit 3 AOS 1 - Biomechanics Principles

Question 1

What is Biomechanics

Answer 1

Biomechanics is the science that studies living things from a mechanical perspectives, tot analyse human movement

Question 2

Quantitative

Answer 2

uses numbers to anaylise movement (km/s, meters per second, newtons of force

Question 3

Qualitative

Answer 3

uses a description of the quality of the performance (to much, not enough, to slow, to fast

Question 4

Kinematics - describing

Answer 4

study of describing movement

Question 5

kinetics

Answer 5

study of forces that course motion

Question 6

linear motion

Answer 6

all body parts are moving together in the same direction in a straight or curved line (such as running)

Question 7

Angular motion

Answer 7

an object or body part moves around a fixed axis

Question 8

Projectile motion - leave ground

Answer 8

when a body or object leaves the ground and is affected only by the force of gravity and air resistance (doing a jump serve in volleyball - objective is to get the ball over the net)

• height of release
• angle of release
• velocity of release

Question 9

general motion

Answer 9

mix of linear and angular motion

Question 10

speed

Answer 10

Speed = distance over time

the rate of motion (km/hr - linear) (Decrease per second or rpm - angular)

Question 11

velocity

Answer 11

velocity = displacement over time

the rate at which an object is changing position (linear) or Rotation (angular)

Question 12

acceleration - velocity

Answer 12

refers to the rate of change in an objects velocity
0 = constant velocity
+ = getting faster
- = getting slower

Question 13

newtons first law - law of inertia

Answer 13

A body will remain at rest or in a uniform motion unless acted upon by an external force
greater mass therefore needs more fore

Question 14

newton second law - law of acceleration
Force = mass x acceleration

Answer 14

refers to the force applied to an object will produce a change in motion in the direction of the force applied

more force = more acceleration
more mass = less acceleration

Question 15

newtons third law - action reaction

Answer 15

for every action there is an equal and opposite reaction

harder you push against something (action force) the harder the reaction force will be, pushing back against us, but in the opposite direction (reaction force)

Question 16

momentum
momentum = mass x velocity

Answer 16

refers to the amount of motion in an object

something with more momentum requires more force
large mass little velocity
smaller ass more velocity

Question 17

summation of momentum

Answer 17

refers to the timing, coordination and sequencing of multiple body parts
allowing athletes to generate maximum force

Question 18

For maximun force - summation of momentum

Answer 18

1. use as many BODY parts as possible
2. SEQUENCE - move the heavier/slower body parts first such as the legs and trunk followed by the lighter/faster body parts such as arms, wrist and fingers
3. TIMING - move the next body part only when the previous body part has reached maximum velocity
4. STABILIZATION - body parts must stabilize once so momentum is not lost

Question 19

impulse
impulse = force x time

Answer 19

refers to the change in momentum of an object
to change momentum in an object, a force must be applied over a period of time
can be an increase to force or increase in time over the force applied

Question 20

Torque
Torque = force x moment arm

Answer 20

cause an object to rotate, the amount of rotations of an object is determined by how much torque is applied and where the torque is applied

Question 21

moment arm

Answer 21

refers to the measure from where the force is applied to the center of rotations. the GREATER the moment arm, the faster the rotation

Question 22

Angular momentum
moment of inertia = mass x radius

Answer 22

refers to the amount of angular motion an object or body has

Question 23

inertia

Answer 23

refers to the tendency for the body to resist a change in its state of motion

Question 24

Greater inertia

Answer 24

more of a resistance to change state of motion = harder to move

Question 25

Lower inertia

Answer 25

less resistance to change state of motion = easier to move

Question 26

conservation of angular momentum angular momentum = moment of inertia x angular velocity

Answer 26

angular motion will remain constant throughout a movement unless their is a external force acting upon the object/body lower M of I = Increase in angular velocity higher M of I = decrease in angular velocity

Question 27

levers

Answer 27

refers to a rigid bar that can be made to rotate around an axis in order to exert a force on another object

Question 28

levers three parts

Answer 28

axis (point of rotation) Resistance (load to move) force (point where the force is applied)

Question 29

first class lever

Answer 29

the axis is between the force and the resistance

Question 30

second class lever

Answer 30

the resistance is between the axis and the force

Question 31

Third Class lever - Need to know

Answer 31

The force is between the axis and the resistance greater range of motion REMEMBER THAT MICLES CROSS OVER JOINTS

Question 32

force arm

Answer 32

is the distance from the axis to the force

Question 33

resistance arm

Answer 33

is the distance from the axis to the resistance range of motion and speed generated can be increased by increasing the resistance arm

Question 34

Mechanical Advantage = force arm over resistance arm

Answer 34

is the amount by which a lever amplifies the force mechanical advantage = force arm / resistance arm mechanical advantage >1 will increase force mechanical advantage <1 will increase speed and range of motion

Question 35

Velocity of release - referring to projectile motion

Answer 35

is the most important factor when trying to maximise he horizontal distance a projectile will travel greater force applied greater velocity release

Question 36

angular of release - referring to projectile motion

Answer 36

is the angle the object is projectile into the air and will depend on the sport release and landing points are the same level the best angle for maximum horizontal distance is 45 degrees

Question 37

hight of release - referring to projectile motion

Answer 37

is the hight projectile is released compared to the hight of the landing point

Question 38

Equilibrium

Answer 38

an object is said to be equilibrium when their are no balanced force or torque acting upon it

Question 39

Balance

Answer 39

the ability to maintain and control equilibrium

Question 40

Stability

Answer 40

being able to control equilibrium

Question 41

center of gravity - stability

Answer 41

refers to the point around which the body weight is balanced, regardless of the position of the body

Question 42

base of support - stability

Answer 42

base of support refers to the area beneath a person including the point of contact between the body and the surface

Question 43

Line of gravity - stability

Answer 43

the direction in which gravity acts is called the line of gravity

Question 44

qualitative movement analysis

Answer 44

is a symmetric approach to analyse performance in skills and to provide feedback to performer about the quality of those skills

Question 45

observation

Answer 45

can be preformed by live and or recorded digitally - what can be observed

Question 46

evaluation

Answer 46

when evaluating the performer, analyist must decide what the problem is what is causing it how can it be addressed

Question 47

validity

Answer 47

refers to the test capacity to measure what it is intended to do

Question 48

reliability

Answer 48

refers to the ability of a test to produce consistant and repeatable results

Question 49

error correction

Answer 49

final step of qualiative analysis weaknesses are identified and strategies to address these are developed