Chapter 9: Biomechanics Flashcards
What is the difference between quantitative and qualitative analysis of biomechanics?
Quantitative is more specific measurements, usually gathered with high-tech tools
Qualitative is based on the quality of the movement and what can be seen and heard
What is the difference between kinematics and kinetics when describing human motion?
Kinematics describes spatial and timing factors without forces
Kinetics, on the other hand, focus on the forces that lead to motion, including internal forces (like muscles) and external forces (like gravity)
What are the 3 models of human motion?
Particle model
Stick figure model
Rigid body segment model
Define inertia
The reluctance of a rotating object to change its state of motion
What are the 3 types of motion?
LINEAR (translation): all body parts move in the same direction, distance, and time (bicycle)
ANGULAR (rotation): body moves in circular motion (summersault)
GENERAL: both at the same time (most)
In a muscular lever system, muscles create _______.
torque
Give examples of 1st, 2nd, and 3rd class levers
1st class: see-saw (posterior neck muscles extending head)
2nd class: wheelbarrow (calf muscle plantarflexing foot)
3rd class: force in between fulcrum and load (biceps flexing elbow — most common class of lever in body)
What are Newton’s laws of motion?
1st — inertia: a body at constant speed (including rest) will remain that way unless acted on by a force
2nd —acceleration: F = ma
3rd — action and reaction
In fluid dynamics there are 2 types of drag. What are they?
Profile drag: caused by the object’s size and shape
Surface drag: caused by the roughness of the object’s surface
What are the boundary layers of surface drag?
Laminar flow, which is smooth and streamlined
Turbulent flow, which is not smooth
The higher the velocity, the (higher/lower) the drag
Higher
A rotating body creating pressure pockets which affect the movement of the object is called _________.
the Magnus effect
What is the difference between static and dynamic equilibrium?
Static equilibrium occurs without the object moving, whereas movement without change is dynamic equilibrium
