Biomechanics Flashcards
Newton’s First Law
Inertia: the body will remain at rest or in uniform motion unless acted upon by an external force
The heavier the object, the greater inertia required to move the force
Newton’s Second Law
Acceleration/Momentum: a force applied to an object will produce a change in motion in the direction of the applied force, proportional to the size of the force
Newton’s Third Law
Action/Reaction: For every action, there is an equal and opposite reaction
Torque
Angular motion caused by an eccentric force, being a force that does not pass through the object’s centre of gravity
Inertia
A measure of how difficult it is to change an object’s motion
Greater inertia = more difficult to change the motion of an object
Angular velocity (tucked vs distributed weight)
The speed of rotation of an object, which will continue rotating unless acted upon by an external force
If mass is located closer to axis of body, it’s easier to rotate than one whose mass is distributed further from axis
First Class Lever
Axis between the resistance and force - to generate great speed or force (eg. crowbar, scissors)
Second Class Lever
Resistance between force and axis - focus on force to increase strength that we can apply to objects (eg wheelbarrow)
Third Class Lever
Force between axis and resistance - focus on speed/ROM as this is the most common lever in the body (eg. bicep curl, kick, throw)
Increase Force Arm
less effort required to move the resistance, acting as a mechanical advantage
Increase Resistance Arm
increase in speed/ROM of movement, more effort required to move resistance, acting as a mechanical disadvantage