Biomechanics Flashcards
Define velocity
The rate of change in displacement
Velocity equation
Velocity (m/s) = displacement (m)/ time taken (s)
Define Momentum
The quantity of motion possessed by a moving body
Momentum equation
Momentum (kgm/s) = mass (kg) x velocity (m/s)
Define Acceleration
The rate of change of velocity
Acceleration equation
Acceleration (m/s^2) = Final velocity (m/s) - initial velocity / time take (s)
Define Force
A push or pull that alters the state of motion of a body.
Force equation
Force (N) = Mass x Acceleration (F=Ma)
Define netforce
The overall force acting on
a body when all individual
forces have been considered.
Define Reaction
Whenever there is a point of contact between two bodies, there will always be a reactionary force.
Define Weight
Gravitational force that the Earth exacts on the body (Downwards).
Define Friction
The force that opposes the motion of two surfaces in contact.
Define Centre Of Mass
The point where the mass of the body tends to be concentrated and balanced in all directions
Newtons 3 laws of motion
N1L - Law of inertia = A body remain in a state of uniform velocity or rest, unless acted upon by an external force.
N2L - Law of acceleration = When a force acts on an object, the rate of change of momentum experienced by the object is proportional to the size of the force and takes place in the direction in which the force acts
N3L - Law of reaction = Whenever an object exerts force on another, there is a force equal in magnitude and opposite in direction, caused by the second object.
Define Fulcrum
Fixed point of rotation about which the lever moves
Define Load
The resistance or weight to be moved. The weight of a human body part to be moved is the load
Define Effort
The force being applied that causes the lever to move. The agonist muscle in the human body
Define load arm
The perpendicular distance from the fulcrum to the load.
Define effort arm
The perpendicular distance from the fulcrum to the effort.
Linear motion
Linear motion is movement of a body in a straight or curved line, where all parts move the same distance, in the same direction, over the same time’.
5 descriptors of linear motion
1) Distance = The total length of the path/ route covered from start to finish
2) Displacement = The shortest straight-line route from start to finish
3) Speed = the rate of change in distance (Distance/Time)
4) Velocity The rate of change in displacement.
5) Acceleration = The rate of change in velocity
Define angular motion
the movement of a body or part of a body in a circular path about an axis of rotation’.
3 descriptors of angular motion
angular velocity
moment of inertia
angular momentum
Define angular velocity
is the rate of change in angular displacement OR
the rate of rotation.
Define moment of inertia
is the resistance of a body to change its state of angular motion or rotation.
Define angular momentum
the quantity of angular motion possessed by a body
Angular motion unit
rad (radians)
Moment of inertia equation
MI = ∑m x r2
Analogue law
A rotating body will continue to turn about its axis of rotation with constant angular momentum unless acted upon by an eccentric force or external torque
Projectile motion
The movement of a body through the air following a curved flight path under the force of gravity
Key factors of projectile motion
1) Speed of release
2) Angle of release
3) Height of release
4) Aerodynamics
Dominant force of a non-parabolic flight path
air resistance
Dominant force of a parabolic flight path
weight
Define a lift force
An additional force created by a pressure gradient forming on opposing surfaces of an aerofoil moving through a fluid or the air
Inverted aerofoil in F1 created by?
Spoiler bar - acts as an INVERTED AEROFOIL, decreasing air velocity over the car.
Front Wing - funnels air underneath car, allowing it to travel at high velocity.
What happens when the magnus effect takes place
As velocity is greater on the opposite side, pressure is lower. The resulting magnus effect will be the projectile moving in the direction of the pressure gradient.
Types of spin
top spin
back spin
side spin - hook or slice
top spin
causes ball to dip/ comes down more quickly/ shorter flight path
back spin
causes ball to float/ travel further/ longer flight path
side spin
causes ball to swerve/ bend/ deviate to left or right/ hook/ slice
