#3.2 u3aos1 - linear and angular concepts of human movement Flashcards
force
1 mark
a push or pull
2 ways force can effect objects
2 marks
-change shape of the object
(stretch, squash, twist)
- move the object
(moving from rest, speeds up, slows down, changes direction)
force formula
1 mark
force = mass X acceleration
explanation:
to move/change shape of an object:
- a mass is obviously required for the object
- acceleration (speeding up) of the mass is required to change its state from still to moving or vica versa
three types of force
3 marks
- friction
- applied force
- gravitational force
friction
2 marks
the contact between two surfaces and
opposes the motion of the object.
applied force
1 mark
force exerted on another object
(kicking a ball, gripping a tennis racket, jumping)
gravitatational force
1 mark
force of attraction between two bodies or objects
angular motion
1 mark
movement of a body part on an axis of rotation (whether real or imaginary)
torque
1 mark
hint: AM
the turning effect caused by a force
and causes change in angular motion
four types of axis angular motion could rotate on?
4 mark
- real
- imaginary
- internal
- external
real axis
1 mark
an axis that is physically detectable
imaginary axis
1 mark
an axis that is not able to be physically identified
internal axis
1 mark
spinning within the body
(how planets spin on its own axis)
external axis
1 mark
spinning outside of the body
(how planets make rotations around other planets)
eccentric force
1 mark
a force that does not act through an object’s centre of gravity
torque formula
torque - force X lever arm
explanation:
- the level arm is a perpendicular distance from the axis of rotation to the line of action.
- torque causes rotation so:
the greater the torque, the greater the angular acceleration
two factors that decide the size of torque
2 marks
- length of lever arm
- size of the applied force
momentum
2 marks
the amount of motion an object has and its RESISTANCE TO MOTION
momentum formula
1 mark
momentum = mass X velocity
explanation:
momentum depends on how fast (velocity) an object (mass) moves.
summation of momentum
3 marks
the sequential and coordinated movement
of each body part
to produce maximum velocity
how is maximal velocity produced via summation of momentum
3 marks
in a sequential matter:
- from body parts closest to centre of gravity to those further away.
- larger muscles to smaller muscles
conservation of momentum principle
2 marks
total momentum of the system before collision is equal to
total momentum of the system after the collision
moment of inertia (MOI)
1 mark
a body’s tendency to resist change in its rotary version
angular velocity (AV)
1 mark
the rate at which you are rotating
