linear motion
movement of a body in a straight or curved line where all the parts move in the same direction and distance over the same time
what causes linear motion
a direct force being applied to the centre of mass of the body
what are the 5 descriptors of linear motion
distance, displacement, speed, velocity, acceleration/deceleration
distance
total length covered from start to finish in meters
displacement
the shortest straight line route from start to finish measured in meters
speed
the rate of change in distance measured in meters per second
velocity
the rate of change in displacement measured in m/s
acceleration
rate of change in velocity measured in M/S/S
deceleration
occurs when the rate of change in velocity is negative
angular motion
movement of a body part or body in a circular path about an axis of rotation
eccentric motion
a force applied outside the centre of mass resulting in angular motion
torque
a measure of the turning (rotational or eccentric) force applied to a body
principle axis of rotation
an imaginary line that passes through the centre of mass about which a body rotates around longitudinal, transverse and frontal axis
transverse
side to side
longitudinal
top to bottom
frontal
front to back
practical example for frontal
cartwheel
practical example for longitudinal
twist/turn
practical for transverse
somersault
angular motion is measured in?
radians
performance
results from an eccentric force being applied outside the body’s centre of mass
what is an eccentric force also known as
torque
three descriptors of angular motion
angular velocity, moment of inertia, angular momentum
sporting example of linear motion
skeleton bob at top speed
sporting example of angular motion
arm rotating about a shoulder joint of a tennis player serving
angular velocity
the rate of change in angular displacement measured in rad/s
angular velocity equation
angular displacement/ time taken
moment of inertia
the resistance of a body to change its state of angular motion or rotation measured in kgm2
what does the moment of inertia depend on
mass and distribution of mass across the axis