more biomechanical terms
DESCRIPTION
An introduction to a few more biomechanical principlesTRANSCRIPT
More More Biomechanical Biomechanical
TermsTerms
InertiaInertia
Inertia is the term used to describe a body's Inertia is the term used to describe a body's resistance to a change in its state of motionresistance to a change in its state of motion
Think of it as an objects resistance to Think of it as an objects resistance to beginning movementbeginning movement
The heavier the object, the greater its inertia The heavier the object, the greater its inertia and therefore the greater the force required and therefore the greater the force required to move it or change its state of motionto move it or change its state of motion
Activity 1Activity 1In pairs, chest-pass the basketball and medicine ball over three distances (1m. 3m, 5m)
1)Which ball has the greater inertia?2)Which ball is easier to throw over longer distances? Why?3)Note which ball is more difficult to catch or stop (this will be referred to again when discussing momentum)
Activity 2Activity 2
Write down 5 sporting examples of InertiaWrite down 5 sporting examples of Inertia
1.1. A stationary soccer ball resting on the A stationary soccer ball resting on the pitchpitch
MomentumMomentum
The momentum of an object is equal to its The momentum of an object is equal to its mass or weight X by its velocitymass or weight X by its velocity
Momentum – Mass X VelocityMomentum – Mass X Velocity
Therefore, an object can only have Therefore, an object can only have momentum if it is moving. The greater its momentum if it is moving. The greater its momentum, the further it may travel and momentum, the further it may travel and the harder it is to stop or slow the objectthe harder it is to stop or slow the object
Activity 3Activity 3
In the above picture, let's say that the mass is 2.0 kg and that the velocity is 4.0 m/s. That is:m = 2.0 kgv = 4.0 m/s
Using the formula work out the objects momentum and express it in kg-m/s
Some MoreSome More
m = 4.36kgm = 4.36kg
V = 15 m/sV = 15 m/s
==
M= 15.47kgM= 15.47kg
V = 35m/sV = 35m/s
==
Activity 4Activity 4
Explain why the principal of momentum is Explain why the principal of momentum is important in sports and sports important in sports and sports competition competition
ImpulseImpulse The concept of impulse is best described by The concept of impulse is best described by
the following formulathe following formula
Impulse= Force X TimeImpulse= Force X Time
In this equation force equals the objects mass In this equation force equals the objects mass X by its acceleration and time equals the X by its acceleration and time equals the length of time for which the force is applied length of time for which the force is applied to the objectto the object
The longer a force can be applied and the The longer a force can be applied and the greater the force applied, the greater the greater the force applied, the greater the objects impulseobjects impulse
Types of MotionTypes of Motion
3 basic forms of Motion3 basic forms of Motion
• Linear
• Angular
• General
Linear MotionLinear Motion
LinearLinear:: ALLALL parts of parts of the body move through the body move through the same distance, in the same distance, in the same direction, in the same direction, in the same timethe same time
List 3 other examples List 3 other examples of Linear Motionof Linear Motion
Angular MotionAngular Motion AngularAngular (rotation): (rotation): The The
body moves in a circular body moves in a circular path around an axis of path around an axis of rotation so rotation so ALLALL parts of the parts of the body move through the body move through the same anglesame angle, in the , in the same same directiondirection, in the , in the same timesame time
List 3 Examples of List 3 Examples of Angular MotionAngular Motion
General MotionGeneral Motion
GeneralGeneral: : Combination of linear and Combination of linear and angular, and is the most common in angular, and is the most common in human movementhuman movement
Sport/Activity Linear Angular General
100m sprint
Tobogganing down a hill
Teeing off at golf
The shoulder in a cricket bowling actionCycling
Going down a slide
An ice skater spinning