SAMPLE Biomechanics PowerPoint

OCR Physical Education
AS / A-Level Biomechanics
PowerPoint Summaries
Herearejustafewsample
slides– wehopeyoulove
them!
Bothteacherandstudent
slidesareincluded(thelatter
willbesuppliedasPDFfilefor
photocopying)
This resource has been written by Ali Woodward for PEfocus and has been designed to support
teaching and learning of the ‘new’ OCR AS and GCE/A-Level PE specification for teaching from
September 2016.
All content mirrors the OCR biomechanics specification perfectly.
The resource comprises:
ü40 full colour / fully animated teacher slides
üStudent slides as PDFs – with gaps to fill (
üTeacher slides as PDFs – with ‘answers’
This resource can be used to present new work, for summing up topic areas and for consolidation
at the end of the course.
We really hope that you and your learners will find it both engaging and helpful.
Biomechanics – student slides
The aim is for students to build their own bank of biomechanics knowledge that can be used
throughout the course as well as at the end for review.
A favoured layout is to print two slides per A3 sheet; this appeals to students who often find the
large visual style manageable, engaging and valuable as a supplement to their other notes and
resources.
Sets of these student slides (PDFs) can be given to students as they start a topic area. They can
work on the set slide by slide as each element of work is completed (e.g. Newton’s Laws); or as a
whole topic area once it has been ‘covered’. This can be done in class or as a homework / private
study task
Student slides can be posted on secure areas of centres’ intranet/moodle platforms for easy
access and further assimilation.
It is highly recommended that students check the accuracy of their work/completed worksheets
against a printed copy of the teacher slides. (NB – agreed Terms and Conditions limit
access to the full colour animated PowerPoint slides to staff only)
1.1
Biomechanicalprinciples:Newton’slawsofmotion
Newton’sfirstlaw:
Lawofinertia
Newton’ssecondlaw:
Lawofacceleration
Newton’sthirdlaw:
Lawofreaction
Definition:Abodywill
remaininastateofrestor
uniformvelocityunless
acteduponbyanexternal
orunbalancedforce.
Definition:Theacceleration(orrate
Definition:Foreveryaction
ofchangeinmomentum)ofabody
thereisanequaland
isproportionaltothesizeofthe
oppositereaction.The
forceappliedandtakesplaceinthe
reactionforceisequalinsize
directioninwhichtheforceacts.
andoppositeindirectionto
f=ma
theactionforce.
Example1:afootball will
remainatrestonthepenalty
spotuntilaforceisapplied
fromtheplayersfoot.
Example1:theaccelerationofanetball
duringapassisproportional totheforce
fromtheplayer’shandsandisinthe
samedirectionastheforce.
Example2:Arunnerwill
remainatconstantvelocityin
themiddle ofaraceunless an
unbalanced forceactson
them.
Therunnerwillaccelerate
forwardsifanunbalanced
forwardsforce(friction)acts.
Example2:Theaccelerationofthe
runnerduringthesprintfinish is
proportional tothesizeofthefriction
forcegeneratedandinthesame
directionasthatforce(forwards)
Example1:whenserving ,a
tennisplayerpushes
downwardsontheground
(actionforce)andtheground
pushes upwardsontheplayer
(normalreactionforce).
Example2:Therunnerpushes
backwardsonthetrack(action
force)andthetrackpushes
forwardsontherunner(reaction
force,inthiscasefriction)
1.1
Biomechanicalprinciples:Newton’slawsofmotion
Newton’sfirstlaw:
Lawof…………………
Newton’ssecondlaw:
Lawof……………………..
Newton’sthirdlaw:
Lawof………………..
Definition:Abodywill
remaininastateof...
Definition:Theacceleration(orrate
ofchangeinmomentum)ofabody
is...
Definition:Foreveryaction
thereis...
Example1:afootball will
remainatrestonthepenalty
spotuntil...
Example1:theaccelerationofanetball
duringapassisproportional ...
Example2:Arunnerwill
remainatconstantvelocityin
themiddle ofaraceunless …
Example2:Theaccelerationofthe
runnerduringthesprintfinish is
proportional to…
Therunnerwillaccelerate
forwardsif…
Example1:whenserving ,a
tennisplayerpushes
downwardsontheground
(actionforce)andthe...
Example2:Therunnerpushes
backwardsonthetrack(action
force)and…
Levers:Classesofleverandmechanicaladvantage
2.2
Leversareclassifieddependingontheorderofplacementofthefulcrum,loadandeffortinthelever
Toidentifytheclassoflever,lookatwhichfeatureisbetween theothertwo…
FLE123
Middlefeature:
Fulcrum=Firstclass
L
E F
Middlefeature:
Load=Secondclass
Plantar
flexion:
fulcrumisthe
ballofthe
foot
E
Elbow
extension
Middlefeature:
Effort=Thirdclass
L
Elbow
flexion
E
F
F
Almostallleversinthehuman
bodyarethirdclass
Mechanicaladvantageofsecondclasslevers
Theeffectofaforcewithinalever
systemdependsontwofactors:
L
1.Thesizeoftheforce:greaterforce=greatereffect
2.Thedistancefromtheforcetothefulcrum:
Thegreaterthedistancethegreatertheeffect
Iftheeffortisfurtherfromthefulcrumthanthe
load,thenlesseffortforceisneededtomovethe
loadand/oragreaterloadforcecanbemoved
Effortarm>loadarm=mechanicaladvantage
Thisappliestosecondclasslevers
Effortarm
E
L
F
Load arm
Mechanicaladvantageofa
second classleverexplains why
theentirebody weightcanbe
movedeasilybycontractionof
thegastrocnemiusduring
plantarflexion
Levers:Classesofleverandmechanicaladvantage
2.2
Leversareclassifieddependingontheorderofplacementofthe________________and
__________inthelever
Toidentifytheclassoflever,lookatwhichfeatureisbetween theothertwo…FLE123
Middlefeature:
Fulcrum=________
Middlefeature:
Load=_________class
L
E F
Plantar
flexion:
fulcrumisthe
ballofthe
foot
E
Elbow
extension
Middlefeature:
Effort=________class
L
Elbow
flexion
E
F
F
Almostallleversinthehuman
bodyare____________
Mechanicaladvantageofsecondclasslevers
Theeffectofaforcewithinalever
systemdependsontwofactors:
1.
2.
Iftheeffortisfurtherfromthefulcrumthanthe
load…
Effortarm>loadarm =
L
Effortarm
E
L
F
Load arm
Mechanicaladvantageofa
second classleverexplains why
theentirebody weightcanbe
movedeasilybycontractionof
thegastrocnemiusduring
plantarflexion
*GCE/Alevelonly
4.5
Linearmotion:Examplesofspeed/timeandvelocity/timegraphs
Aspeed/timegraphshowing
a)Swimmeracceleratingfromthe
start
b)Sprintingattopspeed
c)Stoppingatwall
Avelocity/timegraphshowing
a)Aswimmeracceleratingfromthe
start
b)Sprintingattopspeed
c)Turningatwall
d)Sprintingasecondlength
e)Stoppingatthewall
Speed
(m/s)
b
a
c
Time(s)
Velocity
(m/s)
b
a
c
e
Time(s)
d
Avelocity/timegraphshowing
a)Adiverpushingagainsttheboard
b)Pointoftakeofffromboard
c)Reachingmaximumheightinthe
air
d)Entrytowater
e)Decelerationtobottom ofpool
Velocity
(m/s)
a b
c
Time(s)
e
d
*GCE/Alevelonly
4.5
Linearmotion:Examplesofspeed/timeandvelocity/timegraphs
Foreachofthefollowingexamplesoflinearmotion, drawthegraphontheaxesandlabelpointsa,bandc.
Aspeed/timegraphshowing
a)Swimmeracceleratingfromthe
start
b)Sprintingattopspeed
c)Stoppingatwall
Speed
(m/s)
Time(s)
Avelocity/timegraphshowing
a)Aswimmeracceleratingfromthe
start
b)Sprintingattopspeed
c)Turningatwall
d)Sprintingasecondlength
e)Stoppingatthewall
Velocity
(m/s)
Avelocity/timegraphshowing
a)Adiverpushingagainsttheboard
b)Pointoftakeofffromboard
c)Reachingmaximumheightinthe
air
d)Entrytowater
e)Decelerationtobottom ofpool
Velocity
(m/s)
Time(s)
Time(s)
*GCE/Alevelonly
Projectilemotion:patternsofflightpaths(ii)
7.4
Ifweightissmall,andairresistanceislargethentheflightpathshapeisnonparabolicorasymmetric.Eg:Badmintonshuttle
•
•
•
•
•
Thisisbecausetheforceofairresistanceisabletoovercometheinertia
(smallmass)ofthebody,anddecreaseitsvelocity.
Decreasingvelocitycausesdecreasingairresistance.
Astheflightcontinuesthebodybecomesincreasinglyundertheinfluence
ofitsweight,ratherthanairresistance.
Theparallelogramofforcesshowsthatthesizeoftheresultantforce
decreases,andthedirectionitactsinbecomesfurtherfromthedirectionof
AR.(IncreasinganglebetweenARandR)
Thisgivesanon- parabolicflightshape.
AR
R
W
R
W
Thesizeanddirectionofthe
resultantforceontheshuttle
changesduringflight=
asymmetric,non-parabolicflight
path.
R
W
*GCE/Alevelonly
Projectilemotion:patternsofflightpaths(ii)
7.4
Ifweightissmall,andairresistanceislargethentheflightpathshapeis…
Eg:Badmintonshuttle
Thisisbecausetheforceofairresistanceisabletoovercometheinertia
(smallmass)ofthebody,anddecreaseitsvelocity.
• Decreasingvelocitycausesdecreasingairresistance
• Astheflightcontinuesthebodybecomesincreasinglyundertheinfluence
ofits...
• Theparallelogramofforcesshowsthattheresultantforcechangesin:
a)size:
b)direction:
• Thismakestheflightshape…
•
W
R
Drawtheforcearrowsand
complete theparallelogramon
thediagramsoftheshuttlecock
inmidandlateflight