25.08.2021 Views

082-Engineering-Mathematics-Anthony-Croft-Robert-Davison-Martin-Hargreaves-James-Flint-Edisi-5-2017

You also want an ePaper? Increase the reach of your titles

YUMPU automatically turns print PDFs into web optimized ePapers that Google loves.

226 Chapter 7 Vectors

A

Figure7.3

a

B

Two vectors, → ABand → CD.

C

b

Itispossible toprove the following rules:

D

A

Figure7.4

AB

a

B

c

AD

C

b

CD

Addition ofthe two vectors ofFigure 7.3using

the triangle law.

a +b = b +a vector addition iscommutative

a + (b +c) = (a +b) +c vector addition isassociative

D

ToseewhyitisappropriatetoaddvectorsusingthetrianglelawconsiderExamples7.1

and 7.2.

Engineeringapplication7.1

Routingofanautomatedvehicle

Automatedvehiclesareacommonfeatureofthemodernwarehouse.Sometimesthey

are guided by tracks set into the factory floor. Consider the case of an automated

vehiclecarryingelectricalcomponentsfromstoresatAtoworkersatCasillustrated

inFigure 7.5.

ThevehiclemayarriveatCeitherdirectly,orviapointB.ThemovementfromA

toBcanberepresentedbyavector → ABknownasadisplacementvector,whosemagnitude

is the distance between points A and B. Similarly, movement from B to C is

representedby → BC,andmovementdirectlyfromAtoCisrepresentedby → AC.Clearly,

sinceA,BandCarefixedpoints,thesedisplacementvectorsarefixedtoo.Sincethe

headofthevector → ABtouchesthetailofthevector → BCwearereadytousethetriangle

lawof vector addition tofind the combined effect of the two displacements:

AB + → BC = → AC

Thismeansthatthecombinedeffectofdisplacements → ABand → BCisthedisplacement

AC. We say that → AC istheresultant of → ABand → BC.

C

AC

BC

A

AB

B

Figure7.5

Routing ofan automated vehicle from storesat

Ato workersat C.

Hooray! Your file is uploaded and ready to be published.

Saved successfully!

Ooh no, something went wrong!