Biomechanics 5 Flashcards
what is linear motion
motion in a (straight or curved) line with all body parts moving at the same speed, in the same direction, at the same time
what is distance and it’s equation
how much ground is covered when in motion from one position to another. speed x time (m)
what is displacement and it’s equation
shortest straight line route between two positions. velocity x time (m)
what is speed and it’s equation
the rate at which an object travels a distance. distance/time. (m/s)
what is velocity and it’s equation
the rate of change of speed (or displacement) in a given direction. displacement/time (m/s)
what is acceleration/deceleration with equation
the rate of change of velocity/change on velocity in the time taken to make the change (positive or negative).
change of velocity/time. (m/s^2)
what is linear motion created by
a direct force which passes through the centre of mass of the body
interpret a distance/time graph
- stationary body
/ constant speed
( curved line with decreasing gradient, decreasing speed
) curved line with increasing gradient, increasing speed
interpret a speed/time graph
- constant speed
\ decreasing speed
/ increasing speed/acceleration
( positive but decreasing gradient, accelerating
interpret velocity/time graphs
\ line with increasing negative velocity
, acceleration in a changed direction
/ deceleration in the changed direction (to stop if the line reaches the x axis)
what is newton’s first law
a body continues in a date or rest/uniform velocity unless acted upon by an external force
what is newton’s first law also known as
law of inertia
what is velocity
rate if change in displacement (the shortest straight line route between start and finish). it is speed in a given direction
what is newton’s second law
a body’s rate of change in momentum is proportional to the size of the force applied and acts in the same direction as the force applied
what is the newton’s second law also known as
law of acceleration
how to maximise acceleration
increase size of force (dependent on velocity/speed of equipment) and increase the mass of object used to increase force (heavier equipment to increase acceleration as long as velocity is not lost)
what is newton’s third law
for every action force applied to a body there is an equal and opposite reaction force (eg basketballer jumps and applied force on the ground that applied an equal/upward reaction force on the player)
what is newton’s third law also known as
law of reaction
describe centre of mass
-point at which a body is balanced in all directions- point of concentration of mass
-com changes position and can move outside the body
-can be affected by weight and position of a body
what is stability and what affects it
-ability of a body to resist motion and remain at rest and the ability to withstand force applied and return to its original position without damage (ie balanced)
-position of com: the lower, the more stable
-base of support: the larger the base the more stable
-line of gravity: the more central line of gravity to the base of support the greater
-mass of the body: the greater mass, greater inertia, greater
