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CHS220804 (S1 Reguler)CHS220803E (S1
Ekstensi)
Departemen Teknik Kimia FT!"
#enga$ar % Dr& "r& Sukirn' &Eng"r& Di*an S
&Eng
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e+,ani+s
Stu-ies '. .'r+es an- m'ti'ns
T,ere are se/eral uantities t,at ,a/e t' ea--resse- in t,is -is+ussi'n& T,e rst is .'r+e ,i+, as re/iee- in p,*si+s& T,e unit use- t' measure is 56&
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Flui- e+,ani+s T,e stu-* '. liui-s an- gasses at
rest (stati+s) an- in m'ti'n
(-*nami+s)7 an- t,e .'r+es 'n t,em
"n/'l/es /ari'us pr'perties '. t,e ui-7 su+, as/el'+it*7 pressure7 -ensit*7 /is+'sit*7 sur.a+e tenti'nan- temperature7 as .un+ti'ns '. spa+e an- time&
Flui-s in+lu-e liui-s7 gases7 an- plasmas
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"t is a kn'n .a+t sai- t,at un-er s,ear stress
t,e ui- continuously and permanentlydeformed"t is als' sai- t,at liui- cannot return totheir original state a.ter t,e -e.'rmati'n&
,ile s'li- exhibits a nite deformation,i+, -'es n't +,ange it, time&
Dierences between solids and uids:
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relati'ns,ips '. ui- me+,ani+sran+,es&
Flui- me+,ani+s is a ran+, '.+'ntinu'us me+,ani+s ,i+,-eals it, a relati'ns,ipeteen forces7 motions7 an-statical conditions&
"t -eal it, -i/ersie- pr'lems su+assurface tension7uid statics7ow in enclose bodies7 'row round bodies7 ' stailit*7
t,e 'un-ar* eteen t,e s'li-me+,ani+s an- ui- me+,ani+sis s'me kin- '. gra* area (n't as,arp -istin+ti'n)
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Flui- me+,ani+s -eals it,
t,ree aspe+ts '. t,e ui-
1) Fluid statics: T,e ui- ,i+, is in state '. rest is +alle- as stati+ ui-
an- its stu-* is +alle- as ui- stati+s&
2) Fluid kinematics% T,e ui- ,i+, is in state '. m'ti'n is +alle- as m'/ing ui-&
T,e stu-* '. m'/ing ui- it,'ut +'nsi-ering t,e e9e+t '.e:ternal pressures is +alle- as ui- kinemati+s&
3) Fluid dynamics% T,e ran+, '. s+ien+e ,i+, stu-ies t,e e9e+t '. allpressures in+lu-ing t,e e:ternal pressures 'n t,e m'/ingui- is +alle- as ui- -*nami+s&
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;,at is t,e ne+essit* '. stu-*ing
ui-sas an aspe+t '. engineering
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*ommon &pplications of Fluids
1) +ydroelectric ower lants;ater is use- t' generate ele+tri+it* 'n a larges+ale asis& ;aterst're- in t,e -am p'ssesses p'tential energ*7 ,i+, is +'n/erte-int' t,e ele+tri+al energ* in t,e p'er generati'n unit '. t,e plant&
H*-r'ele+tri+ p'er plants are 'ne '. t,e ma$'r suppliers '. p'ert,r'ug,'ut t,e 'rl-& "n s'me +'untries p'er reuirements are.ullle- entirel* * t,ese plants&
,) +ydraulic machines T,e ui- ,as t,e +apa+it* t' li.t ,ea/* l'a-s an- e:ert e:tremel*
,ig, pressures& S'me ,*-rauli+ ma+,ines are use- t' per.'rm/ari'us ma+,ining 'perati'ns&"n m'st '. t,ese ma+,ines7 'il is use- as t,e ui-& T,e 'il is passe-t,r'ug, t,e ,*-rauli+ m't'r ,i+, trans.ers large am'unts '.energ* t' t,e ui-& T,is ,ig, energ* ui- enters t,e pist'n an-+*lin-er arrangement ,ere it +an e use- t' li.t ,ea/* l'a-s 'r
appl* large .'r+es&
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-) &utomobilesFlui-s per.'rm t,ree +ru+ial 'perati'ns in aut'm'iles% generati'n '.p'er7 luri+ati'n7 an- +''ling '. t,e engine&#etr'l7 re.erre- t' as .uelgenerates p'er 'n +'musti'n in t,eengine&=il is use- .'r t,e luri+ati'n '. t,e enginegear':/ari'us 't,erm'/ing parts& ;ater is use- .'r +''ling t,e engine&
.) /efrigerators and &ir *onditionerst,e ui-s are kn'n as re.rigerants& T,e re.rigerant as'rs t,e ,eat .r'm ,ate/er is eing kept in t,e+,iller 'r e/ap'rat'r (at a l' T) an- -eli/ers t,at ,eat t' t,eatm'sp,ere(s at a ,ig, T)& "n air +'n-iti'ners7 t,e re.rigerant as'rsr''m ,eat an- t,r's it in t' t,e atm'sp,ere7 t,ere* keeping t,er''m +''l&
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2) Fluids as a /enewable #nergy ource>ir 'r in- is 'ne '. t,e m'st p'pular s'ur+es '. reneale energ*&;in- is use- .'r generati'n '. ele+tri+it* 'n a smalllarge s+ale
asis&;ater is use- in ti-al p'er plants t' generate ele+tri+it*&=+ean a/es are use- t' r'tate turine la-es it,in t,e p'erplant& ?i'-iesel7 a t*pe '. t,e /egetale 'il7 is use- as a .uel .'r/e,i+les&
3) !perating 4arious %nstrumentsC'mpresse- air is use- .'r t,e 'perati'n '. /ari'us t*pes '.aut'mati+ /al/es& T,ese /al/es +an e a+ti/ate- an- -ea+ti/ate- *appl*ing t,e pressure '. +'mpresse- air& T,e pneumati+ t''ls ,i+, 'rk 'n +'mpresse- air are use- .'r/ari'us appli+ati'ns like grin-ing7 s+reing an- uns+reing /ari'us
ma+,iner* parts7 et+&
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S!?D"@"S" EK>5"K> FA!"D>
HBDR>!A"CS % t,e ' '. ater in ri/ers7 pipes7 +anals7 pump7 turines
HBDR=A=B % t,e ' '. ater in t,e gr'un-
RESER@="R ECH>5"CS % t,e ' '. 'il7 gas an- ater in petr'leum
reser/'ir
>ER=DB5>"CS % t,e ' '. air ar'un- aer'planes7 r'+ket pr'$e+tils ETE=R=A=B % t,e ' '. t,e atm's.eer
#>RT"CAE DB5>"CS % t,e ' '. ui- ar'un- parti+les (-ust settling7
slurr*7 pneumati+ trans.'rt7 ui-ie- e7 air p'llutant parti+les)
!AT"#AE#H>SE FA=; 'il ell7 +aruretirs7 .uel in$e+t'r7 +'musti'n+,amer7 spra*s&
@"SC=!S D="5>TED FA=; luri+ati'n7 in$e+ti'n m'l-ing7 ire +'ating7/'l+an'es7 +'ntinental -ri.t
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"n-ustrial appli+ati'n
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Storage
Valves
Pipe
Pump
Flowmeter
Process Equipment
D">R> =F FA!"D FA=; SBSTE
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iping ystems
1) #ump72) #r'+ess euipmentan-
3) C'ntr'l euipment
pr'/i-es t,e energ*nee-e- t' '/er+'met,e resistan+e t' '
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#eri'-e 2001112
Ae+tures %
Rau7 13%001G%30 EC%104
?EF=RE i- Test #ak Sukirn' >.ter i- Test #ak Di*an S
Tut'rials % >sisten
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>ssessment
#ak Kirn' G0 2G % i-Test (2 $am)
10 % Iui (in +lasstut'rial)
1G % >ssigment
Nilai P.Kirno x 50% + Nilai P.Diyan x 50% Nilai =
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?''ks
5'el -e 5e/ers Flui- e+,ani+s .'r C,emi+alEngineer7 Se+'n- E-&
C'uls'n J Ri+,ar-s'n C,emi+al Engineering7@'l 17 Ge (1L) ?utter'rt,Heinemann
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Aess'n #lans =utline
STATIC FLUID APPLICATIONVessel ti!"ness #esi$n &eas're(ent o) *ress're Se*aration o) )l'i#s it #i))erent #ensity Desi$n o) si* y#ra'li! ,a!"
F-ICTION LOSSS ON PIP S/ST& FO- LI1UID23asi! )l'i# )lo4is!osity !ontin'ity e6.(ass 7alan!e2 3erno'lli ner$y 7alan!e2 &oo#y #ia$ra( )ri!tion )a!tor
Fri!tion loss !al!'lation in *i*elines syste( *i*e si8e #esi$n P'(*9s ner$y re6'ire(ent.
PU&P AND PU&PIN: S/T&Centri)'$al P'(* P'(* Desi$n
FLO; &ASU-&NTT'7e Pitot t'7e ori)i!e(eter ent'ri(eter rota(eter area(eter2
FO-CS DU TO FLO; T
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5eek
0 "5TR=D!CT"=5 1 >ssigment
1 STATIC FLUID APPLICATION To*i! ?2 1 Ae+turing7 H;
2 F-ICTION LOSSS ON PIP S/ST& FO-LI1UID To*i!@2
2 Ae+turing7 H;
3 PU&P AND PU&PIN: S/ST& To*i!2 2 Ae+turing7 H;
4 FLO; &ASU-&NT To*i!B2 3 Ae+turing7 H;
G FO-CS DU TO FLO; T
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DEF"5"T"=5 =FFA!"D
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C'mm'n Flui-s
Aiui-s% ater7 'il7 mer+ur*7 gas'line7 al+','l
asses% air7 ,elium7 ,*-r'gen7 steam
?'r-erline% $ell*7 asp,alt7 lea-7 t''t,paste7 paint7
pit+,
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;,at is a Flui-<
6 a substance which deformscontinuously under the action of
shearing forces howe7er small8
6 unable to retain any unsupportedshape9 it takes up the shape of any
enclosing container8
888 we assume it beha7es as acontinuum
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T,e ui- is mainl* -i/i-e- int' t' +ateg'ries% liui-s an-gases&
T,e main -i9eren+e eteen t,e liui-s an- gases state ist,at gas ill '++up* t,e ,'le /'lume ,ile liui-s ,as analm'st : /'lume&
;,atNs t,e -i9eren+e<
Hen+e7 t,e pressure ill n't a9e+t t,e /'lume& "n gase'us p,ase7
an* +,ange in pressure -ire+tl* a9e+ts t,e /'lume&
T,e gas lls t,e /'lume an- liui- +ann't& as ,as n' .reeinter.a+esur.a+e(sin+e it -'es ll t,e entire /'lume)&
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'iuids: Cl'se pa+ke-7
str'ng +',esi/e .'r+es7
retains /'lume7 ,as .ree sur.a+e
Aiui-s an- gasses O ;,atNs t,e-i9eren+e<
Li6'i#
Free S'r)a!e
:as
x*an#s
;asses: ;i-el* spa+e-7
eak +',esi/e .'r+es7.ree t' e:pan-
>lm'st in+'mpressileRelati/el* eas* t' +'mpress
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#er.e+t as Aa
PV = nRT
R is t,e uni/ersalgas +'nstant T is in Kel/in
Note #eiation )ro( te textH Note #eiation )ro( te textH
Use a7sol'te *ress're )or P an# a7sol'te
te(*erat're )or T
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@ap'r #ressure
0
?000
@000
000
B000
5000
000
E000
000
0 ?0 @0 0 B0
Te(*erat're C2
V a * o r * r e s s
' r e 0 P a 2
liui-
;,at is /ap'r pressure '. ater at 100PC
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Sur.a+e tensi'n is -ene- as t,e tensile .'r+e a+ting 'n t,esur.a+e '. a liui- in +'nta+t it, a gas 'r 'n t,e sur.a+eeteen t' immis+ile liui-s su+, t,at +'nta+t sur.a+e
e,a/es like a memrane un-er tensi'n&
Sur.a+e tensi'n '. t,e ui- is measure- in terms '. sur.a+eenerg* per unit area 'r .'r+e per unit lengt, mainl* e+auseit a+ts 'n t,e sur.a+e& "t is -en'te- * s*m'l (sigma)& T,eS" unit '. measurement '. sur.a+e tensi'n is 5m an- its KS
unit is kg.m&
ater stri-er +analk 'n ater< ra'r la-e is'ating 'n t,e
,e sur.a+e tensi'n
gi/es sp,eri+al s,apet' ater -r'ps&
5hat is the urface "ension of theFluid
http://www.brighthub.com/guides/energy.aspxhttp://www.brighthub.com/guides/energy.aspx
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Interesting Examples of Surface Tension in our Day-to-Day Life
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4) =ercury used in the thermometer% T,e mer+ur* use- in t,et,erm'meter -'es n't sti+k t' t,e all '. t,e +apillar* tuee+ause '. t,e sur.a+e tensi'n& Ha- it stu+k t' t,e alls t,e
measurement '. temperature 'ul- n't ,a/e een +'rre+t&G) eparation of oil and water% T,e separati'n '. 'il an- ateris +ause- -ue t' t,e -i9eren+e in sur.a+e tensi'n '. t,e t'liui-s& T,ere is als' separati'n '. t,e .uel an- luri+ating 'il in t,eengine -ue t' t,eir sur.a+e tensi'n& Ha- t,e* mi:e- t'get,er7 t,e.uel 'ul- ,a/e l'st its +'musti'n pr'perties ,ile luri+ating 'il
'ul- ,a/e l'st its /is+'sit* an- luri+ati'n pr'perties&L) oap bubbles% =r-inaril* t,e ules in ater are unstale7ut ,en sur.a+tants are intr'-u+e- in ater its sur.a+e tensi'n isre-u+e- * .a+t'r '. t,ree 'r m're& "n su+, ater t,e ules +anremain stale ,en+e l'ts '. ules are seen in su+, liui-s&
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T,e 'le+ular =rigin '. Sur.a+e Tensi'n
"malan+e '.interm'le+ular.'r+es e:ists att,e liui-airinter.a+e
γ la t,esur.a+e tensi'n
t,at e:ists att,e liui-airinter.a+e
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T,e m'le+ule > is +'mpletel*insi-e t,e ui- an- it isattra+te- * +',esi/e .'r+es
'. t,e surr'un-ing m'le+ulesin all -ire+ti'ns& T,eresultant .'r+e a+ting 'nm'le+ule is er'&
t,e m'le+ule ? l'+ate- at t,e sur.a+e '. t,e ui-& T,ere are-'nar- .'r+es '. attra+ti'n 'n t,is m'le+ule -ue t' 't,er
m'le+ules& T,us t,ere is net resultant .'r+e a+ting 'n m'le+ule? in t,e -'nar- -ire+ti'n& T,us t,e .ree sur.a+e '. t,e ui-
a+ts like a /er* t,in lm un-er tensi'n '. t,e sur.a+e '. t,e
liui- a+ts as t,'ug, it is an elasti+ memrane un-er tensi'n
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Capillar* >+ti'n
T,e ten-en+* '.liui-s t' rise up
in narr' tues +apillar* a+ti'n&
Due t' t,ep,en'men'n '.
sur.a+e tensi'n&
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Capillar* Rise
T,e pressure e:erte-* a +'lumn '. liui-is alan+e- * t,e
,*-r'stati+ pressure& T,is gi/es us 'ne '.
t,e est a*s t'measure t,e sur.a+etensi'n '. pure liui-s
an- s'luti'ns& @
@
@ @
ghr
ghr
r ghr
ρ
γ
ρ γ
π ρ π γ
=
=
=
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T,e C'mpli+ati'n '. C'nta+t>ngles
T,e alan+e '. .'r+es t,at resultsin a +'nta+t angle7 θ +&
T,e +'nta+t angle gi/es
in.'rmati'n 'n t,e ettailit*N '.a sur.a+e&
@!os
@
@ @
ghr
ghr
r ghr
ρ θ γ
ρ γ
π ρ π γ
=
=
=
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". a tue is suU+ientl* narr' an- t,e liui- a-,esi'n t' its alls issuU+ientl* str'ng7 sur.a+e tensi'n +an -ra liui- up t,e tue in ap,en'men'n kn'n as +apillar* a+ti'n& T,e ,eig,t t,e +'lumn isli.te- t' is gi/en *
Re-+'nta+t angle less t,an 0Plue+'nta+t angle greater t,an 0P
C>#"AA>RB R"SE >5D F>AA
". is greater t,an 0P7 as it, mer+ur* in a
glass +'ntainer7 t,e liui- ill e -epresse-
rat,er t,an li.te-&
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F'r a aterlle- glass tue in air at stan-ar- la'rat'r*+'n-iti'ns7 γ 0&0M28 5m at 20 PC7 θ 20P (0&3G ra-)7 ρ is1000 kgm37 an- g &81 ms2& F'r t,ese /alues7 t,e ,eig,t '.t,e ater +'lumn is
T,us .'r a 4 m (13 .t) -iameter glass tue in la +'n-iti'ns gi/en a'/e (ra-ius2 m (L&L .t))7 t,e ater 'ul- rise an unn'ti+eale 0&00M mm (0&00028 in)&H'e/er7 .'r a 4 +m (1&L in) -iameter tue (ra-ius 2 +m (0&M in))7 t,e ater'ul- rise 0&M mm (0&028 in)7 an- .'r a 0&4 mm (0&01L in) -iameter tue (ra-ius0&2 mm (0&00M in))7 t,e ater 'ul- rise M0 mm (2&8 in)&
http://en.wikipedia.org/wiki/Radianshttp://en.wikipedia.org/wiki/Radians
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=aximum bubble pressure method
@
.(ax cap R p
∆
=σ @
.(ax cap
R p∆=σ
?ule pressure tensi'meter pr'-u+es gas ules (e:& air) at +'nstant rate an- l's t,em t,r'ug, a+apillar* ,i+, is sumerge- in t,e sample liui- an- its ra-ius is alrea-* kn'n&
T,e pressure (P) insi-e '. t,e gas ule +'ntinues t' in+rease an- t,e ma:imum /alue is 'taine-,en t,e ule ,as t,e +'mpletel* ,emisp,eri+al s,ape ,'se ra-ius is e:a+tl* +'rresp'n-ing t' t,era-ius '. t,e +apillar*&
>7 ?% > ule appears 'n t,e en- '. t,e+apillar*& >s t,e sie in+reases7 t,era-ius '. +ur/ature '. t,e ule-e+reases&C% >t t,e p'int '. t,e ma:imum ulepressure7 t,e ule ,as a +'mplete,emisp,eri+al s,ape ,'se ra-ius isi-enti+al t' t,e ra-ius '. t,e +apillar*-en'te- * R+ap&
http://en.wikipedia.org/wiki/Tensiometerhttp://en.wikipedia.org/wiki/Pressurehttp://en.wikipedia.org/wiki/Pressurehttp://en.wikipedia.org/wiki/Tensiometer
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Sur.a+e Tensi'ns '. #ureAiui-s at 23 K
Substance γ / (10 -3
N/m)
Acetone 23.7
Benzene 28.8
ar!on"etrac#lori$e 27.%
&et#'lene (o$i$e )%.8
*ater 72.8
&et#anol 22.+
n,-eane /8.0
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∆ pπ
R@ @π
Rσ
#ressure in+rease in a sp,eri+al -r'plet
R
p σ @
=∆
R
p σ @
=∆
∆ pπ R@
@π Rσ
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0.0500.055
0.000.050.0E00.0E50.00
0 @0 B0 0 0 ?00
Te(*erat're C2
S ' r ) a
! e t e n s i o n 0 N J ( 2
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E:ample% Sur.a+e Tensi'n
Estimate t,e -i9eren+e in pressure (in#a) eteen t,e insi-e an- 'utsi-e '. aule '. air in 20WC ater& T,e air
ule is 0&3 mm in -iameter&
R p
σ @=
R p
σ @=
R 0&1G : 103 m
σ 0&0M3 5m ( )
(?0?5.0
NJ(0EA.0@
−×
= p ( )
(?0?5.0
NJ(0EA.0@
−×
= p
GE0 Pa p SGE0 Pa p S
;,at is t,e -i9eren+e eteen
pressure in a ater -r'plet an- in an
h p γ = h p γ = ater (?.0JG0
GEB
===m N
Pa ph
γ ater (?.0
JG0
GEB
===m N
Pa ph
γ Stati+sQ
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>5 D>S>R EK>5"K> FA!"D>
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Every ody continues in its state of rest% or ofuniform motion in a straight line% unless it iscompelled to change that state y forces impressedupon it!
5et'nYs First Aa '. 'ti'n
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m F a =
The acceleration produced y a particular force acting ona ody is directly proportional to the magnitude of the
force and inversely proportional to the mass of the ody!
"he econd 'aw in &ction
am F .=
m g F
mr
mG F
g
earth g
.
..@
=
=
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=ass and 5eight
T,e ,an-ling '. mass an- eig,t -epen-s 'n t,e s*stems '.units t,at is use-& T,e m'st +'mm'n s*stems '. units aret,e"nternati'nal S*stem &'
" = m a )$*where" = force )+*m = mass ),g*
a = acceleration)m-s. *
T,e eig,t 1 kg mass +an e e:presse- as%
/ = m g ).*where/ = weight )+*m = mass ),g*
g = acceleration of gravity)m-s. *
w = )$ ,g* )0!123 m-s. *= 0!123 )+*
a= "-m= $ + -$,g=$ m-s. *
T,e .'r+e 15 a+t 'n 1kg mass%
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?ritis, ra/itati'nal S*stem 4#
T,e unit '. mass7 t,e slug7 is -eri/e- .r'm t,e p'un-.'r+e *
-ening it as t,e mass t,at ill a++elerate at 1 .''t per se+'n- perse+'n- ,en a 1 p'un-.'r+e a+ts up'n it%
3 ase units in t,e "mperial s*stem are .t7 s7l.
$ l = )$ slug*)$ ft-s. *
;it, a stan-ar- gra/it* g = 5.!$3627 ft-s. O
=n t,e eart,t,e mass '. 1 slug eig,ts 5.!$3627 lf
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Englis, Engineering S*stem EE
the asic unit of mass is lm * and the force is lf
$ lf ill gi/e a mass '. $ lm a stan-ar- a++elerati'n '. 5.!$3627
ft-s.&
" = m a - gc )5*
whereg
c = a proportionality
constant
$ lf = )$ lm *)5.!$36 ft-s
.
* - gcorg
c = )$ l
m *)5.!$36 ft-s. *-)$ l
f *
c
mg W
g =
c
mg W
g =
$ slug = 5.!$3627 lm
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$! /AN: S-IN: &&3IN:UN:KAN
@ @@ @.?Em mc
f f
lb lb ft mg ft g
W lb s lb s= = =
@ @@ @.?Em mc
f f
lb lb ft mg ft g
W lb s lb s= = =
@
G.F0D
I ?G.F0D
m
c
mkg
mg s g W N
= =
@
G.F0D
I ?G.F0D
m
c
mkg
mg s g W N
= =
@!(G0.
s ?G0. #yne
m
c
g mg
g W
= =
@!(G0.
s ?G0. #yne
m
c
g mg
g W
= =
Eng S*stem
S" S*stem
CS S*stem
$ lm ( 'n eart, g5.!$3627 ft-s.&) ill gi/es
1l.
$,g mass ( 'n eart, g0% 128 m-s. ) ill gi/es780L 5
$g mass ( 'n eart, g0% 128 cm-s. ) ill gi/es 780L-*ne
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Se+'n-ar* !nits
F'r+e
5 kgms2 (5et'n)
l. slug.ts2 (p'un- .'r+e)
32&2 lm.ts2 ;'rk (F'r+e t,r'ug, a -istan+e)
Z 5m (Z'ule)
.tl. (.''t p'un-) Energ* (;'rk per time)
; Zs (;att).tl.s (.''t p'un- per se+)
,p GG0 .tls (,'rsep'er)
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Conersion o) Units