Biomechanics Principle Flashcards
What is Newtons first law
Law of inertia- a body will remain in a state at rest unless acted upon by a external force
what is Newtons second law
law of acceleration- the acceleration of a body is the same to the size of the force applied and takes place in the same direction
what is Newtons third law
law of reaction- the reaction force is equal in size and opposite in direction to the action force
definition of a force
a push or pall that tends to alter the state of a body
if forces work together the effect is combined
if act against it has a cancelling effect
what forces act on a body when it is vertical force
- weight
- reaction force
what forces act on a body when it is horizontal force
- friction
- air resistance
definition of centre of mass
the point at which a body is balanced in all direction
what is centre of mass affected by
- shape
- density of different parts of the body
what is stability
a measure of how easily a body is moved from a position of balance
definition of a balanced force
when two or more forces acting on body are equal in size but opposite in direction
definition of a unbalanced force
when two or more forces acting on a body do not cancel out
definition of net force- resultant force
the overall force acting on a body when all forces are considered
factors affecting friction
surface area
weight
temperature
how can friction be maximised
- increase roughness surface
- increase mass
- increase temperature
factors affecting air resistance
velocity
frontal cross sectional area
streamlining and shape
surface characteristics
how can air resistance be minimised
- reducing frontal cross sectional area
- using streamlined shape
- making surface smooth
line of gravity
an imaginary line extending vertically downward to the ground from centre of mass
base of support
the area enclosed by the points of contact with ground
how is a body most stable
- low centre of mass
- large base of support
- line of gravity in middle of bas of support
