Linear Motion, angular motion, fluid mechanics and projectile motion (1.3b) Flashcards
linear motion is….
movement of a body in a straight line where all parts move the same distance in the same direction over the same time
direct force is….
and what does it result in?
a force applied through the centre of mass resulting in linear motion
in a distance time graph the gradient of the curve indicates the…
speed of the body
in a speed time graph the gradient of the curve indicates the…
acceleration or decleration of the body
in a velocity time graph the gradient of the curve indicates the…
acceleration or deceleration of the body
angular motion results from an…
eccentric force being applied to a body outside its centre of mass
torque is…
a measure of the turning force applied to a body
the logitudinal axis runs from….
the top to the bottom of the body
a practical example that uses the longitudinal axis is…
a trampolinist performs a full twist turn
the transverse axis runs from…
side to side of the body
a practical example that uses the transverse axis is…
a front somersalt
the frontal axis runs from….
the front to back of the body
a practical example that uses the frontal axis is….
a gymnast perfoms a cartwheel
the three axis of rotation are…
longitudinal
transeverse
frontal
angular analogue of moment of inertia is…
the resistance of a body to change its angular motion or rotation
moment of inertia =
sum (mass x distribution of mass from axis of rotation^2)
angular velocity is….
the rate of change in angular displacement or rate of rotation
moment of inertia is measured in…
kgm^2
angular velocity =
angular displacement / time taken
angular velocity is measured in…
rad/s
angular momentum is…
the quantity of angular motion possessed by a body
angular momentum =
moment of inertia x angular velocity
angular momentum is measured in…
kgm^2/s
the two factors that affect moment of inertia are…
mass
ditribution of mass from the axis of rotation
what effect does mass have on moment of inertia?
the greater the mass the greater the moment of inertia, the harder it is to change the rate of rotation
what effect does distribution of mass from the axis of rotation have on moment of inertia?
the further the mass from the axis of rotation the greater the moment of inertia so there is more resistance to rotation
what affect does a high moment of inertia have on angular velocity?
the resistance to rotation is high therefore angular velocity is low and rate of spin is slow
what affect does a low moment of inertia have on angular velocity?
the resistance to rotation is low therefore angular velocity is high and rate of spin is fast
define conservation of angular momentum
angular momentum is a conserved quantity that remains constant unless an eccntric force or torque is applied
does angular momentum once generated change throughout movemrnt?
no
performers manipulate ___________ and _______ to maximise performance
moment of inertia
angular velocity
define the angular analogue of newtons first law of motion
(the angular equivalent of Newton’s first law of motion)
a rotating body will continue to turn about an axis of rotation with a constant angular momentum unless acted on by an eccentric force or torque
define drag
the force that opposes the direction of motion of a body through water or air
the 4 factors that affect air resistance and drag are…
velocity
frontal cross-sectional area
streamlining and shape
surface characteristics