Biomechanics Flashcards Preview

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Flashcards in Biomechanics Deck (28)
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1
Q

Law of inertia

A

Body will continue in a state of uniform velocity unless acted upon by an external or unbalanced force

Push or pull that alters the motion

2
Q

Law of acceleration

A

A bodys rate of change in momentum is proportional to the size of the force applied and acts in the same direction as the force is applied

The more force, the further it will go

3
Q

Law of reaction

A

For every force applied, there’s an equal opposite reaction force

4
Q

Velocity and equation

A

Rate of change in displacement

Velocity = displacement/time taken

5
Q

Momentum and equation

A

Quantity of motion possessed by a moving body

Momentum = mass X velocity

6
Q

Acceleration and equation

A

Rate of change in velocity

Acceleration = (final - initial velocity) / time taken

7
Q

Force and equation

A

A push of pull that alters the state of motion of a body

Force = mass X acceleration

8
Q

What are internal/external forces

A

Internal
- Generated by skeletal muscle

External

  • Outside the body and acts upon in
  • Gravity, friction, air resistance
9
Q

Five effects of forces

A
Can create motion
Can accelerate a body
Can decelerate a body
Can change the direction of a body
Can change the shape of a body
10
Q

What is net force

A

The overall motion of the body when all external forces are taken into account

11
Q

Vertical forces

A

Weight, arrow down from centre of mass
Weight (N)= mass (kg) X acceleration (m/s/s)

Reaction, arrow up from ground

12
Q

Horizontal forces

A

Friction, affected by roughness/temperature of surface and size of normal reaction

Air resistance, affected by velocity, shape, front cross sectional area and smoothness

13
Q

What is included on free body diagrams

A

Weight (down)
Reaction (up)
Air resistance (opposite direction)
Friction (same direction)

14
Q

Horizontal acceleration

A

Friction > air resistance

15
Q

Vertical acceleration

A

Reaction > weight

16
Q

Balanced forces

A

Weight = reaction

Constant velocity

17
Q

What are limb kinematics

A

Movement in relation to time and space
3D motion analysis using computer software
Data produced immediately and is highly accurate
Helps coaches to select areas for improvement
Specialised, expensive, lab conditions

18
Q

Force plates

A

Ground reaction forces
Lab conditions
Jumping, balancing, running on force plates
Gait analysis, balance and rehabilitation
Immediate, accurate, reliable results
Specialised, expensive, lab conditions

19
Q

Wind tunnels

A

F1 teams
Aerodynamics of cars
Reducing drag
Specialised, expensive, complex analysis

20
Q

What is the centre of mass

A

Point that a body is balanced in all directions
Can be outside the body as a point of rotation

Around naval in anatomical position
Womens slightly lower than mens

21
Q

What is stability and factors affecting it

A

Ability of a body to resist motion and remain at rest

  • Mass of body increase, stability increase
  • Lower COM, stability increase
  • Larger base of support, stability increase
  • Line of gravity in line with base, stability increase
22
Q

Features of leaver systems

A

Lever (bone)
Fulcrum (joint)
Effort (muscular force)
Load (weight/resistance)

23
Q

Lever classifications

A

123=FLE

Each feature in the middle
Most are 3rd class

24
Q

Efficiency of lever systems

A

Distance from fulcrum is the effort arm
Distance from load to fulcrum is the load arm

Longer levers generate greater forces
Greater the distance of effort from fulcrum, the more significant the load becomes

25
Q

Mechanical advantages/disadvantages

A
Seconds class have advantage
Effort always longer than load
Large load with small effort
Efficiency over a small range of motion

Third class have disadvantage
Load longer than effort
Large effort to move a small load
Move load at high velocity and generate acceleration

26
Q

Transverse axis of rotation

A

Sagittal plane of movement
Spin front or back
Through one side of the body to the other

27
Q

Longitudinal axis of rotation

A

Transverse plane
Round on the spot, 360degrees
Straight down body from head to toe

28
Q

Frontal axis of rotation

A

Frontal plane

Through the tummy