Biomechanical Principles Flashcards
Define Linear Motion
Motion in a straight or curved line, with all body parts moving the same distance at same speed in same direction
Define Newton’s first law of inertia
A force is required to change the state of motion
Example of Newton’s first law of inertia
In a penalty, a ball will remain on the spot unless it’s kicked by the player (an external force is exerted upon it)
Define Newton’s second law of Acceleration
The direction and magnitude of the force determines the direction and magnitude of acceleration
What is the equation for Newton’s second law of acceleration
F=MA
Example of Law of acceleration
When player kicks ball during game, the acceleration of ball is proportional to size of force. Harder it’s kicked, further and faster it will go in direction force applied
Define Newton’s third law of motion
For every action, there’s an equal and opposite reaction
Example of Newton’s 3rd law of motion
When footballer jumps up to win header, a force is exerted on ground in order to gain height. At same time, ground exerts upward force on player
Define ground reaction force
The equal and opposite force exerted on performer who applies a muscular force on ground
Define scalar quantity
When measurements are described in terms of just their size or magnitude
What are 2 scalar quantities
Speed and distance
Define Centre of mass
The point of balance
Define line of gravity
The line extending vertically downwards from CoM
What are factors affecting stability
–Height of Com
–Position of the line of gravity
–Area of support base
–Mass of the performer
How does the height of Com affect stability
Lowering the Com will increase stability
