3.1 Biomechanics Flashcards
4 things biomehcanics allows performers and coaches to do
Analyse performance
Maximise movement efficiency and technique
Reduce or prevent injuries
disgn/chose correct equipment
how to write 1 metre per second
1 m/s
newtons first law and what does it state
Law of inertia
A body continues in state of rest or uniform velocity unless acted upon by an external or unbalanced force
velocity definition
rate of change in displacement
inertia definition
resistance of body to change its state of motion whether at rest or moving
newtons second law and what does it state
Acceleration
A bodys rate in change of momentum is proportional to size of force applied and acts in same direction as force applied
newtons third law and what does it state
Reaction
for every action force applie there is an equal and opposite reaction force
velocity equation
velocity = displacement/time taken
velocity units of measurment
m/s
momentum definition
quantity of motion possesed by a moving body
momentum equation
Momentum = mass X velocity
Momentum units of measurement
Kgm/s
Acceleration definition
rate of change in velocity
acceleration calculation
acceleration = (FV-IV)/time taken
what is force
push or pull that alters state of motion of a body
Force calculation
force= mass X acceleration
units of measuremnt acceleration
m/s/s
units of measurment for force
Newtons
5 effects of force
create motion accelerate a body decelerate a body change direction of body change shape of a body
Net force deinition
Sum of all forces acting upon a body of known as resultant force
weight definition
gravitational pull that earth exerts on a body measured in N
Weight calculation
mass x acceleration due to gravity
friction definition
Force that opposes the motion of two surfaces in contact measured in N
4 factors that affect friction
Roughness of ground surface ( Increased roughness increased friction)
Roughness of contact surface
Temperature ( increased = increased friction)
Size of normal reaction
Air resistance definition
Opposes motion through air
4 factors affecting air resistance
Velocity ( increasing = increasing)
Shape - aerodynamic = less resistance
Frontal cross sectional area
smoothness of surface
What is streamlining
creation of smooth air flow around an aerodynamic shape to minimise air resistance
All the things needed n a free body diagram
Weight ( down from COM) Reaction ( up from point of contact) Friction (same direction as motion) air resistance ( opposite direction of movement) Direction of movement
Limb kinetics
3D or optical motion analysis allowing limb efficiency to be evaluated with measurements of displacement, velocity and acceleration in multiple planes of movement
Good things about limb kinaetics
Date produced is immediate, objective and accurate used by coaches to adjust and improve technique
Bad things about limb kinetics
accuracy depends on correct placement of body markers
doesn’t cater for individual differences
specialised expensive equipment
what are force plates
plates that measure ground reaction forces used to work out size and direction of forces, acceleration rates, work and power output
benefits of force plates
Immediate accurate reliable results used to analyse performance
negatives of force plates
Specialist expensive and in loab conditions which could change the way some performers jump/ run compare to real life
what are wind tunnels and what is their aim
creates wind so engineers can look for ways of reducing drag
