Teacher's/Lecturer'sSheet
Printed:30.03.201714:37:27|P1001000
Blockandtackleformedfromalooseandafixed
pulley(ItemNo.:P1001000)
CurricularRelevance
AreaofExpertise:
Physik
EducationLevel:
Klasse7-10
Subtopic:
Kräfte,einfache
Maschinen
Topic:
Mechanik
Experiment:
Flaschenzugauseiner
losenundeinerfesten
Rolle
Difficulty
PreparationTime
ExecutionTime
RecommendedGroupSize
Intermediate
10Minutes
20Minutes
2Students
AdditionalRequirements:
ExperimentVariations:
Scissors
Keywords:
Taskandequipment
Informationforteachers
AdditionalInformation
Thestudentsshouldrecognizeonasimpleblockandtacklethattheforcerequiredtoliftaspecificloadcanbereducedbyhalf
comparedwiththeweight(force)byusinganarrangementof2pulleys.However,alongerdistancemustbecovered.By
comparingtheproductsload×loaddistanceandforce×forcedistancetheyshouldrecognizethatbothareequallarge.
Theterm“(slotted)weight"isincorrectinasmuchaswearedealingwithamasswhichbecomesaweight(inreality“aweightforce")undertheinfluenceoftheearth’sgravity.Theterm“masspiece"usedhereisbetter.
Robert-Bosch-Breite10
D-37079Göttingen
Tel:+49551604-0
Fax:+49551604-107
[email protected]
www.phywe.com
Student'sSheet
Printed:30.03.201714:37:27|P1001000
Blockandtackleformedfromalooseandafixed
pulley(ItemNo.:P1001000)
Taskandequipment
Task
Doesablockandtacklereduceforce?
Setupablockandtacklewithamoveableandafixedpulley,andbecomefamiliarwithitsmodeofoperation.
Liftvariousloadswithitanddeterminethevalueofloadandforceforeachcase.
Liftacertainloadwiththeblockandtackleanddeterminetheloadandforcedistances.
Robert-Bosch-Breite10
D-37079Göttingen
Tel:+49551604-0
Fax:+49551604-107
[email protected]
www.phywe.com
Student'sSheet
Printed:30.03.201714:37:27|P1001000
Equipment
PositionNo.
Material
OrderNo.
Quantity
1
Supportbase,variable
02001-00
1
2
Supportrod,stainlesssteel,l=250mm,d=10mm
02031-00
1
3
Supportrod,l=600mm,d=10mm,splitin2rodswith 02035-00
1
3
Bosshead
02043-00
1
4
Weightholderforslottedweights
02204-00
1
5
Slottedweight,black,10g
02205-01
4
5
Slottedweight,black,50g
02206-01
3
6
Pulley,movable,dia.65mm,w.hook
02262-00
1
7
Pulley,movable,dia.40mm,w.hook
03970-00
1
8
Rodforpulley
02263-00
1
9
Springbalance,transparent,2N
03065-03
1
10
Measuringtape,l=2m
09936-00
1
10
Fishingline,l.20m
02089-00
1
Set-upandprocedure
Set-up
Firstscrewthesplittsupportrodtogether(Fig.1).Setupastandwiththesupportbase(Fig.2).Pushthe25cmsupportrod
throughtheholeofthesupportbaseandtightenitwiththelever(Fig.3).Putthelongsupportrodinthesupportbase(Fig.4).
Robert-Bosch-Breite10
D-37079Göttingen
Tel:+49551604-0
Fax:+49551604-107
[email protected]
www.phywe.com
Student'sSheet
Printed:30.03.201714:37:27|P1001000
Fig.1
Fig.2
Fig.3
Fig.4
Fixthepulley(d=65mm)tothe"rodforpulley"(Fig.5).Tiealoopineachendofa120cmlongpieceoffishline.Fixoneend
ofthefishlineontherodforpulley(Fig.6).Clamptherodwiththebossheadonthelongsupportrod(Fig.7).
Fig.5
Fig.6
Robert-Bosch-Breite10
D-37079Göttingen
Tel:+49551604-0
Fax:+49551604-107
[email protected]
www.phywe.com
Student'sSheet
Printed:30.03.201714:37:27|P1001000
Fig.7
Usethesmallpulleyasmovablepulley,hangthesecondendofthefishlineonthe2Nspringbalanceandfixitonthe25cm
supportrod(Fig.8).
Fig.8
Procedure
Determinetheweight(force)Frofthemovablepulleyandnoteitinthereport.Afterthat,hangtheweightholderonthe
movablepulley;addmasspiecessothattheloadis50,100,150and200g(Fig.9).Forhangingtheslottedweightupthe
weightholder,youshouldsliptheslottedweightoverthetopoftheweightholder(Fig.10).
Robert-Bosch-Breite10
D-37079Göttingen
Tel:+49551604-0
Fax:+49551604-107
[email protected]
www.phywe.com
Student'sSheet
Printed:30.03.201714:37:27|P1001000
Fig.10
Fig.9
DeterminetheforceFforeachmassonthelooseendofthelinewiththespringbalance(Fig.11);recordthemeasuredvalues
inTable1.
Fig.11
Use100gasaloadandremovethespringbalance.
Allowtheloadtorestonthetableandpullthelinetaut.
Turnthefixedpulleysothatitsmarkingpointpointstotheright.
Tieaknotinthelineatthelocationofthefixedpulley'smarkingpoint(Fig.12).
Pullonthefreeendofthelinediagonallydownwardasfaraspossible;measurethelengthofthelinesfbetweenthe
markingknotandtherightsideofthefixedpulley.
Measurethedistanceslwhichtheloadhasbeenraised(Fig.13).
Recordthemeasuredvaluesinthereport.
Robert-Bosch-Breite10
D-37079Göttingen
Tel:+49551604-0
Fax:+49551604-107
[email protected]
www.phywe.com
Student'sSheet
Printed:30.03.201714:37:27|P1001000
Fig.12
Fig.13
Inordertodisassemblethesupportbaseyoushouldpresstheyellowbuttons(Fig.14).
Fig.14
Robert-Bosch-Breite10
D-37079Göttingen
Tel:+49551604-0
Fax:+49551604-107
[email protected]
www.phywe.com