Bio-mechanics 2 Flashcards
What is a lever system formed by?
forces, axis of rotation and moment arm
What is a first class lever?
axis of rotation is in the middle and effort and resistance are on two sides
ex. AO jt is axis of rotation
What is second class lever?
resistance is located between the axis of rotation and the effort
this provides a mechanical advantage
ex. calf raise- AOR is MTP jt, effort is plantar flexors, resistance is gravity
What is third class lever?
effort is located between axis of rotation and resistance
most common in body
no mechanical advantage but excursion advantage
What is momentum?
mass X velocity
if no velocity no movement
In order to stop the momentum of an object what do you need to do to the object?
apply a force to that object over a period of time aka generating impulse
What is impulse?
force X time
What is work?
Force x displacement
What type of muscle movement is involved with positive work?
concentrically working muscle—-generating energy
What type of muscle movement is involved with negative work?
eccentrically working muscle—-absorbing energy
What type of muscle movement is involved with no work?
isometrically working
What is energy?
energy is the capability for the system to do work
What are the two types of energy?
kinetic and potential
What is potential energy?
energy due to position or stored energy
M x G x H
What is kinetic energy?
energy due to motion
1/2mv^2
