Biomechanics, Linear CH- 12

3 Aspects of Force

Direction of Force Amount of Force Pont of Application

Direction

Direction of a force is along its action line

Law of Reaction

For every action there is an equal and opposite reaction. F = -F

Law of Acceleration

The acceleration of an object is directly proportional to the force causing it and inversely proportional to the mass of the object. F=ma

Force is.....

a vector quantity: - Magnitude and direction - Also has a point of application

Internal Forces

are muscle forces that act on various structures of the body.

External Forces

are those outside the body: Weight, gravity, air or water resistance, friction, or forces of other objects acting on the body.

Force

is that which pushes or pulls through direct mechanical contact or through the force of gravity to alter the motion of an object.

Impulse

The product of force and the time it is applied. Impulse=FT

Momentum

The product of mass and velocity. M=MV

Law of Inertia; Newton's First Law

(A body continues in its state of rest or of uniform motion unless an unbalanced force acts on it) - an object at rest stays at rest AND an object in motion stays in motion unless acted on by an outside force (F not equal 0)

Weight is....

Mass times acceleration due to gravity: W=Mg (weight is mass x gravity)