PE: biomechanics
what is biomechanics
science of studying living things from a mechanical perspective
what is force
a push or pull of an object
what is acceleration
change in speed in response to time measured in m/s/s
what is mass
amount of matter that makes an object
what is friction
a force that acts in the opposite direction to motion when two surfaces are in contact with each other
what is gravitational force
pull objects with mass towards each other
what is air resistance
known as drag friction that opposes motion which occurs between air and another object
what is water resistance
force that uses friction to slow things down moving through water
what is weight
measure of gravitational force acting on the body measured by weight=m x gravity
inertia
an object that is resistant to change in its state of motion
momentum
mass x velocity something with mass that is moving
velocity
displacement divide by the change in time
conservation of momentum
isolated system total momentum of two or more bodies acting upon each other remain constant unless an external force is applied
Summation of momentum
sum of all movements to apply a force
impulse
amount of force applied to an object and duration its applied
newtons 1st law inertia
law of inertia a body will remain at rest unless acted upon by an external force
newtons 2nd law acceleration
law of acceleration force applied to an object will produce a change in acceleration in the direction of the applied force
newtons 3rd law action/reaction
every action has an equal and opposite reaction
linear motion
movement of the body part around an axis of rotation
torque
measure of all force that can cause an objrct to rotate spin
angular momentum
something that is spinning mass x velocity x radius
radius
radius is the point from rotation to the part you strike something
moment of intertia
closer the mass is distributed to the axis of rotation the easier it is to rotate the further away the mass the harder to rotate
conservation of angular momentum
when no external force acts on an object there is no change of angular momentum eill occur
displacement
the change in position of an object
speed
distance divided by change in time
eccentric force
a force that doesn't act through an object, centre of gravity causes an object to rotate and move foward
centre of gravity
point in which the whole weight of an object equal in all directions
line of gravity
an invisible line that passes through the centre of gravity in the direction that gravity acts
base of support
the area underneath your feet
balance
ability to control equilibrium while stationary or moving
balance
ability to control equilibrium while stationary or moving
stability
abilty of a body to resist a change on its current state of equilibrium
dynamic equilibrium
state where bodies are moving at a constant velocity
equilibrium
where all forces and torques are balanced
static equilibrium
a state where bodies are at rest
angular distance
total of all angular changes of a rotating body
angular displacement
the difference between initial and final angular position of a rotating body
angular speed
the angular distance travelled divided by the time it took to cover the distance
angular velocity
rate of change of angular displacement over time
angular acceleration
rate of change of angular velocity
projection motion
movement of an object through the air
angle of release
angle at which a body or object is projected in the air in relation to horizontal
speed of release
the speed of a projectile at the instant of release
height of release
general rule increasing how high we release an object will result in more air and distance travelled.