Linear Kinetics (Biomechanics) PDF

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lecture notes on linear kinetics, Newton's laws of motion ...

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Biomechanics lecture- Linear Kinetics Linear Kinetics is concerned with the underlying causes of translation, and of changes in that translation. Forces All linear motion can be traced back to forces that are applied to the body or object. A force applied to an object will always tend to change the object’s velocity (unless other forces prevent that…) Forces are vectors, so they have:   

Magnitude Direction A point of application

to determine how an object will be accelerating, we need to identify all of the external forces acting on that object. (Internal forces are those acting within the object – for example, a tendon pulling on a bone and its reaction –and they cancel out) external forces can include:  

Gravitational forces (weight) contact forces: pushes or pulls acting at an interface between the object and the outside world, impact forces, fluid forces (air resistance)

Newton’s Laws  



1st law- Law of Inertia- An object will remain at rest, or moving with constant velocity, unless it is acted upon by a net external force. 2nd law- Law of Motion- An object’s acceleration is proportional to the net force acting on the object and is in the same direction- The acceleration is inversely proportional to the mass of the object. 3rd law- Every action has an equal and opposite reaction. Forces occur in equal and opposite pairs....