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OKPY*HOCTb pa,.uHyca h, ITJIOCKOCTb KOTOpofr ITepiTeH,UHKYJIHpHa o:::H spameHHH, a ueHTp C Jie)KHT Ha ca:,wii: ocn. EcnH 3a speMH dt nponcXOLI.HT 3JieMeHTapHbiH rroaopoT TeJia Ha yro.1 df:P, TO T04Ka M npH 3TOM cosepwaeT B.UOJib csoeii: TpaeKTopnu 3JieMeHTapHoe rrepe:.IerueHHe ds=

Tor.na 4HcJiosoe 3Ha4eHHe cKopoCTu T04KH 6yn.eT pasHo OTHO-

weHH!O ds K

dt, T. e.

dm

 

d~

 

V=dt= h dt

HJIII

v = hffi.

 

 

(44)

CKopOCTb

V B OT.'IH4HeOT yr.'IOBOHCKOpOCTll TeJia H33b!BaiOT HHOrll.a

erue /lUHeUflOU HJ!H OKpy'J/CHOii CKOpOCTb!O TO'IKII M.

TaKHM o6pa30M, ttUCAoaoe 3Hatt.eHue cxopocmu mottKU epaUJf110ll{EcOCR meepaoco me;w paeHo npou3eeaeHUIO yc.!loaoii cKopocmu me!la Ha paccmoRHtte om :;moii mottKll iJo ocu epau;.eHufl.

HaiTpaBJieHa CKOpOCTb ITO KaCaTeJibHOH K OIIHCb!BaeMOi'f T04KOII OKPY*HOCTH rwn ITepiTeH,.uHKy.'IHpHomwc:wcru, ITpoxo,.uHruefr qepe3 ocb sparueHnH u TO'IKY M.

TaK KaK ,U.'IflBCeX TO'-IeKTeJia (f) HMeeT B ,UaHHbl!f MOMeHT BpeMeHH OLI.HO l1 TO JKe 3Ha4eHHe, TO H3 ¢op~1y.'Ibi (44) CJie,.uyeT, 4TO CKOpOCTH

T04eK sparuaiO:uerocH TeJia rrpoiTopuiioHaJibHhi nx paccTOHHIIHM OT ocu

BparuemrH. 00JI2 C!WpoCTefi TO'!eKBpaill,a!OlUCfOCH TBep,.uoro TeJia HMeeT BHLI., ITOKa3~HHblH Ha pHC. 136.

Pv.c. 135

2.

Y c K o p

e H H n T o q

e K T e JI a .

.Unrr Haxo:JKn.emrH ycrwpc-

HliH

TO'-IKH M

BOCITOJib3yeMCH

cpopMyJia~.!H

a,=dv'dt, an=V2 /p.

B Hawe~.l CJiyqae r=h. no.'l;CTaB.TJH5l 3HatiCHUe v H3 paBeHCTBa (4~)

B BbipaJKeHHH at H an, ITOJIY'IHM:

dw h~w2

ar=hdT' an=h

(45)

KacareJibH?H COCTaBJIHIOIUa51 ycKopemm a, narrpaB.TJeHa ITO KaCaTe.'lbHOli K TpaeKTOpHH (B CTOpOHy ,UBHllieH!Ili IItJH ycKopeHHOM :sparueHHii TCJia H B Oopamy;o CTOpOHy ITpH 3aMeJJ,JieHHm1); HOpMaJibHa51

COCTaB.1HIOIU35I an BcerJ].a HanpaeJieHa no pa,.uuycy LVI c K OC!l sparueHH}1 (pHc. 137).

123

DoJIHoe ycKopeHIIe T04KII M 6y,JJ,eT a = Va~+a; IIJIH

 

a=hVs2 -l-w'.

(46)

0TKJIOHeHHe BeKTOpa ITOJIHOrO ycrwpeHHH OT pa,JJ,uyca OITHCbiBaeMOH T04KOH OKpy)KHOCTII OITpeL(eJ!fieTCH yrJIOM J-1, KOTOpb!H Bbi4HCJIHeTCH ITO

¢opMyJie

tg[1=a,/an [BTopaH

H3 ¢opMyJI (22)]. DoL(craBJIHR CIO)J,a 3Ha-

qeHHH a,;

ll an H3 paBeHCTB

(45), IT?JiytraeM

 

 

 

tg f1=B/cu 2

(47)

TaK KaK cu u s HMeiOT B ,JJ,aHHb!H MOMeHT speMeHH L(JIH scex T04eK TeJia 0):\HO ll TO )Ke 3Ha4eHIIe, TO H3 QJOpMyJI (46) II (47) CJieL(yeT, 4TO ycKopeHHH scex TotreK Bpaw;aiOw;erocH TBep,JJ,oro TeJia ITpoiTopuuoHaJibHbl HX pacC-TOHHHHM OT OCII Bpam;eHI15I ll o6pa3yiOT 1;3 ,JJ,aHHb!H MOMe!IT BpeMeHH O,JJ,HH H TOT 1Ke yroJI f1 C paL(HycaMII OITHCb!BaeMbiX Hl\iH OKpy)K- HOCTef.f. TioJie ycKopemn1 TotreK npaw;aiOmerocH TBep,JJ,oro TeJia HMeer BH,JJ,, llOKa3aHHbiH Ha pHC. 138.

PHc.

138

Puc. 139

¢opMyJibl (44) -

(47) TI03l30Jl5IIOT orrpeL(e.II!-!Tb CKOpOCTb H ycKopeHHe

JIIOOOH TO'IKHTeJia, eCJII1 li3BeCTeH 33KOH Bpam;eHIIH TeJia H paCCTOHHHe L(aHHOH TOqKH OT OCH Bpaw;eHHH. Do 3TH~ li{e <!JopMyJia~ MO)i{HO, 3HaH

,JJ,BH)KeHHe 0):\HOH TO'IKHTeJia, Ha}iTi! L(B!DKeHIIe JIIOOOH L(pyro:ii ero T04KH,

a

TaK)Ke xapaKrepHcriiKII ,JJ,BmKemm

scero

reJia B

ueJioM.

.

3. B e K T 0 phi C K 0 p 0 C T 11

II y

C K 0 p

e H 11 H T 0 q e K

T e JI a. 4TOObl HaHTH Bbipa)KeHHS'IHerrocpe,JJ,CTBeHHO L(JIH BeKropOB V H

a, rrpone,JJ,e~ 113 ITpOI13BOJibHOH roqKH

0 OCH AB paL(Hyc-BeKrop

rT04KH

M (pHc. 139). TorL(a h=r sin a n

ITO cpop:-.-ryJie (4·1)

 

IvI= I(!) Ih =I(!) Ir sin a

mm IvI= f'W X r

 

T aKHM o6pa30M, - MOL\YJib BeruopHoro ITpOH3BeL(eHHH ffi X r paBeH Mo)i"yJIIO CKOpOCTH TO'IKHM. HanpaBJieHHH BeruopoB wX r II v TO)Ke cosiTa,JJ,aiOT (o6a OHH rrepiTeHL(IIKYJIHpHbi ITJIOCKOCTH OMB) u pa3MepHoCTH ux OL(HHaKOBbi. CJie)J,onareJihHO,

V=wXr,

(48)

124

T. e. BeKmop cKopocmu AI06oii mo•u\.u epaU{a!Owp.ocfl meAa paeeH eeKmopHOMY npou3eeaeHUIO YcAoeou CKOpocmu meAa Ha paauyc-eeKmop amoii tnOtiKU. ¢OpMyJiy (48) Ha3b!BaiOT cpOpMyJIOH 3ii:Jiepa.

Bepa or o6eux qacTeii paseHcTBa (48) rrpou3BOJJ.Hbre no speMeHH, llOJIY4HM

HJIH

 

a = (eX r) +(@Xv).

(49)

ci>opMyJia (49) oiTpeJ].emrer BeKrop ycKopeHHH moooii T04KH spamaiOmerocH reJia.

BeKrop BX r HarrpaBJieH, KaK II BeKTOp ffi X r, T. e. ITO KaCaTeJibHOH K TpaeKropuu TO'IKHM, a (exrl=er sin a=eh. BeKTop *e wxv HaITpaBJieH BJJ.OJib MC, r. e. ITO HopMaJiu K rpaeKropuu ro4KH M, a lw x Xv\=wvsin 90°=w2h, raK KaK v=wh. Y4HTbiBaH see ::~ru pe3yJihTaThr, a TaK>Ke cpOpMyJibi (45), 3aKJIIO'!aeM, 'ITOeXr ~ H ruXV=a11

3a)J.a'la 54. BaJI, ,!(eJ!aJOW:HH n=90 o61MHH, nocJie BbiKJIIO'IeHHH ,!(BHraTeJia na- 'IHHaeTnpaw:aThCR panno3aMe!l,.TieHHO H OCTaHaB.'IHBaeTcRqepe3 t1=40 c. OnpeAeJIHTb, CKOJibKO o6opOTOB Cl\eJiaJ! B8•1 3a 3TO BpCMH.

p e Ill ell He. TaK K3K BaJ1 BpamaeTCH paBH03aMe,!(J!eHHO, TO J],JlH Hero, C'IHTa5!

<i'o=O, 6y,!(eT

(a)

HaiJaJibHOH yr.ITOBOH CKOpOCTblO npH 3aMC,!(J!eHHOM Bpaw:eHHH HBJIS!eTcH Ta, KoTopyro BaJI HMeJI AO BbTKJIJO'!eHHHADHraTeJia. CJie,!(oBaTeJibHO,

 

 

w0=nn130.

B MOMeHT OCTaHOBKH

llllH f=f1

yrJ!OBa5! CKOpOCTb BaJia, w 1=0. IlO,!(CTaBJillH STR

8Ha'leHH5! BO BTOpoe H3

ypaBHeHHH

(a), I!OJiyqaeM:

O=:rtn/30+ct1 H e=-:rtn/30t1.

ECJIH o6o3Ha'IHTbqHcJio c,!(eJiaHHblX BaJJOM 3a apeMSI t1 o6opoToB qepea N (He CMeiiJHBaTb C n; n - yrJIOB35! CKOpOClb), TO yroJI IIOBOpOTa 38 TO JKe BpeM5! 6y,!(eT paBeH <p1 =2:rtN. ITO,!(CTaBJI5!H H3H,!(elliii>le 3Ha'leHH51 e H q1 B nepnoe H3 ypaBHeHHH (a),

TIOJIY'IHM

2nN= (nn/30)t1-(nnj60) t1 =(:rtn/60)ti,

N= nt11120=30 o6.

3a,IJ.a'la55. l'vlaxoBHK paAuycoM R=0,6 M npam,aerca paBHOMepHo, ,IJ.eJiaa n= =90 o6fMHH. Onpe,!(eJIHTb CKOpOCTb H ycKopeHHe TO'IKH,JieiKalll.eH Ha 060,!(e M3XOBHKa.

p e lii e H H e. CKopOCTb TO'!KH o6o,IJ.a V=R W, r,!(e yrJIOBa5! CKOpOCTb W ,ll.OJIJKH3 6h1Tb BblpaiKeHa n paAHaHax B ceKyHAY· TorAa w=nnl30=3:rt a v=R·3:rt~5,7 M/c•

.UaJiee, TaK KaK w=const, To e=O, H, cJie,IJ.oBaTeJihHO,

a=an=Rw2=R·9n2~53,3 Mlc2

YcKopeHHe TO<[KH HanpaBJieHO B ,!(3HHOM cJiyqae KOCH Bpaw:eHHH.

 

3a,IJ.aqa 56. IloJiaraH, 'ITOnpH pa3rone MaXOBHK npaw:aeTCH no saKoHy

 

cp = c0 +c1f +Cze-kt,

(a)

onpe,IJ.eJIHTb 3HaqeHR5! noCTORHHbiX Ko:;,¢¢mJ,HeHTOB c0 , c1 , c2 H k H3 ycJioBHH, 'lTDnpH t=O ,1:\0JIJKHO 6b!Tb t:p0 =0 H W0=0 H 'ITOnpe,!(CJibH35! yrJIOBa5! CKOpOCTb, ,ll;O KOTOpofi

125

pasroHHeTCH MaxoBHK Wnp=50 c- 1 , aero ynwBoe ycKopeHne npa pasro11e ne )l;OJJJKHO npeBbiiiJaTb 3H3'leHUHeH= 10 c- 2. HaihH Ta!oKe, KaKoe ycKopen:ae 6y.r~eT npn 9TOM y TO'leKo6o.r~a \13\0BHKa B MOMeHT spC11enn t1= l c, ecJm pa;~.nyc MaxosnKa R=0,4 M. p e llJ e H He. l13 ypaBHeHHH (a) BH)l;HO, 'ITOllpH t=O <p~O, ecJJH c0+c2=0, T. e.

c0=-c2

 

 

,'J.a.1ee!!3 ypaBHeHUH (a) HaxonnM, liTO w=~=c1-kc2e-kt. CJieJJ.oBaTeJ!.bHo, npu

t=O lu~O, Cl\~11 c1 -kr2 =0, T. e. c1~kc~.

 

 

IlpH smx 3Ha'lell!ll!Xc0 H c1 ypannerme (a) npn:,leT Bllil.

 

<p=c2 (kt+~:-"1 -1).

(6)

0Tcro,:z.a naxo;<mi

 

 

 

 

(B)

I1epnoe !13 paBeHCTB (B) noKa3wBaeT,

'ITO w co Bpe\Jene\I pacTeT n npu

f-'>-=

crpC\1l!TCH K npeJ1eJibllOMY sna'lenmoc~k;

c.1c;zonareJibHO, W 0 p=c2k. H3 BToporo JKe

paBCHCTBa Bll;J.llO, 'ITOC cO BpeMeHe~l YCblB<l~T, CTpCWlCb ({ ny,IIO, a t·JaH60.~bU:ee 3Ha-

'!CHne c2k"

nMeeT npn t= 0;

cJJe;wsaTem.uo,

f'H"--Czk2.

 

 

 

w0 ,=50

c- 1 11

 

Ho no

ycijOBI!HM sana<m

f 11 = 10 c- 2.

Tor.r~a /I.0.1lh.l!O 6biTb' c"k=50, a

c;!~z~ 10, omy.ua k=0,2 H c2=2)0. -I1pn 31HX

3lW'leH<!llX k H C2 paBeHCTBO

(6) /1.8eT OKOH'lll·

1e.%HO C.1e.Z::'>Cllilllr3aKOH BpaW,ellHH MaXOBl-IKa:

 

cp=253(0,2t+e-~·2l-l).

(r)

 

Tor,:;.a, 'l10sn;~.no H aa paBeHcTB (s), 6y-

p,er

"

 

 

 

 

 

 

w=58 (l-e-o,2\ e= 10e-o,21.

(,l\)

PHC, 14.0

.1_.-q MO\leHra BpeMeHH

f1= 1 C,

Y'lHTbl-

 

B3Sl,

<no e- 0 2:=o:0,82, no.1y'l!nr ffi ""9,0 c-1,

e ""8,2 c- 2. CJie/I.OBaTeJibHO, B 3TOT MOMeHT npeneHH a,=Rc

 

 

1

 

1

=3,3 M1c2, a =Rw2=

1

 

 

 

11

 

=32,4 Mlc2 n a=Vai+a~=32,6 M,'c.2

3aJI.aqa 57. rpys B (pnc. l40l npncopnT ao rparr enne ra,T panrrycm-r r n cn,c~.H· ill)'lOHa O,!(HOH OCH C B3JIOM llJCC1epH!O J pa~h:\CC\1 r1 . Ll,BHJKeHHe rpysa H3'llmaeTCH 1!3 COCTOHHHH IIOKOH II npOHCXO,JHT C !lOl'TOlHIJlbl\1) CKopeHHeM a. 0npe,c~.e.1!1Tb, IIO K3· KOMY saKoHy oyJieT np11 3TOM BpammvcH H3~\0,'!i'IL(a>.cH B 3a:J.enJien,m c mccrepHeii 1

rnecrcpHH 2 pa.J:Hyet M rz·

P em e 11 H e. TaK KaK rpya B H3'1l-lllaeTJJ.Pllr3TbCH 6e3 Ha'la.1bHoi1 cKopocTH, TO era CKOpOCTb B JII06oii MO~IeHT Bper,Je!lll t p:lSHa Cf (vs=af). 3ry CKOpOCTh uy,ayr

l!MeTb H TO'!KH 060J1ll BaJJa. Ho, C !L(lyroii CTO(JOHH, CKOpOCTH 3fHX TO'leKpaBI!bl w1r, r,!(e w1- o6ruaH ;J.JJH BaJia H rnccTepHH 1 yrJJoBall chopocrh. C1ei'\oBaTe.'lbHO,

w1r=at, w1 =ai'r.

Teneph rmi'!.'I,eMUJ 2. TaK KaK

rKopocTb TO'-lKII C([en.leHI!H C ,c~.oJIJKHa 6L1Th O)l;HOH

H TOH JKe Jl.JlH o6eux mccTepcH,

10 z·c=w1r1 "--WJz, orKy,!(a

W2 = (r1 'r2)w1 =(r1a r"r)t.

HTaK, yrJronaH cKopocTh meCTepHH 2 pacreT nponopnuona.JJhHO BpCMCHH. Yt!llThiBaH, '!TOw2=dlh'dt,r.r~e <p2 - yroJ! nosopora mecrepna 2, no.'ly'IIIM

dcp1= (r 1 a'r2r)ldt.

0TC!0,!(3, 6ep5! OT o6eHX 43CTCH HHTerpaJib! H C'lliT351,'ITOllpH f=Q yro.'!<p2=01 Hall/I.CM OKO!!'laTeJibHOsaKOH paBnoycKope!!HOfO Bp<?.lll,Ct!Hfl lllCCTepHll 2 B BH,!(e

<p2= (r1 a:'2r2r)t2

* 3Ha'leHHe(I) MOMeT H3MeHHTbCll !10 3aKOHY (JI), KOf.Ila Ha MaXOBIIK .'leilcTBYIOT !10CT05!HHblll Bpalll,a!Olll,HH MOMei!T H MOMeHT CH.'lconpOTHB.lJeHHll, nponOpi.\HOHaJlbHbiH w (3a/l.a'la 150 B § 128).

126

JJ.HHaThl xA, YA
142).
Pacc~tOTpiTM ceqeniTe S
PHC. 141

rnasa XI

OJIOCKODAPAJIJlEJlbHOE ~BR>KEHME TBEP~OfO TEJIA

§52. YPABHEHlUI flJIOCKOflAPAJIJIEJihHOfO ABH)I(EHH.SI ~BH)I(EHH.SI llJIOCKOfl «<lHfYPbl).

PA3J10)1(EHHE ABH)I(EHH51 HA flOCTYOATEJlbHOE H BPAJ.UATEJibHOE

llMcKonapaA.Ile.1bHb/.Jft (mm nAoCKU.M) Ha3bwaemcH maKoe OBUJ/Cettue meepaoco meAa, npu Komopo.M ece eco mottKu nepeJdeU{momcH napaAAeAbHo HeKOmopoii cpUKCUpOBaHHOU nAOCKOCtnU ll (piTC. 141). fJJIOCKOe )].B!ltKeHITe

coBepwaiOT MHoriTe '!aCTITMexaHH3MOB IT Marrnm, nanpiTMep KanmJ.eecH KOJieco na npHMOJIITHeiinoM Y':WCTKe nyTI-I, waTyH B KpHBownnHononsyHHOM MexaHIT3Me IT JJ.p. LJ.acTHbiM cnyqaeM rrnocKonapanneJihHoro )].BHJKeHITH HBJIHeTCH BpaiiJ,aTeJibHOe )].BITJKe!IITe TBep)].OrO TeJia BOKpyr HeOO)].B!DKHOif OCIT.

y

PHc. 142

TeJia KaKofr-HHOYJJ.h ITJIOCKOCTbiO Oxy, rrapa.'I- JieJihHOif IT.'IOCKOCTH fl (piTC. 141). f1piT IT.'IOCKOITapaJIJieJibHOM )].Bl!JKeHITH Bee TOl!KIT TeJia, Jie)KaiiJ,He Ha rrpm>1oii MM', rreprreHJJ.HJ{YJIHpnoii ceqeHITIO S, T. e. nnocKOCTIT TI, JJ.Bin!<yTcB TO)KJJ.eCTBeHHO.

OrciO)].a saKJIIOtraeM, liTO )].JIII IT3yl!eHHH JJ.B!ltKeHITH Bcero TeJia JJ.Oc· TaTOl!HO IT3Yl!ITTh, KaK JJ.BH:rKeTcn B ITJIOCKOCTH Oxy ceqenue S 3Toro TeJia ITJIH HeKOTOpaH ITJ10CKMI 4J11rypa S. f103TOMY B )].aJibHei'uneMBl'.JeCTO ITJIOCKOrO )].BIT)!{eHIUI TeJia oy)].eM paccMaTpiTBaTb )].BIT)KeH!Ie ITJIOCKOlf ¢nrypb! s B ee ITJIOCKOCTIT, T. e. B ITJIOCKOCTH Oxy. T1piT 3TOM Bee pe3YJihTaTbi, KOTOpbre OYJJ.YT rronytreHbi B § 53-59 )].JIH TO'!eK rrnocKo!"r ¢ITryphr, cnpaBe.!l.Jll1Bhi, KOHetrno, IT )].JIH Tol!eK cetieHITH S TBep)].oro TeJia, lJ.BHJKyUJ.erDCH ITJIOCKOITapaJIJieJibHO.

T1oJIO)Kemre ¢Hryphr S B rrnocKOCTH Oxy orrpe)].eJIHeTC5I rroJIOJKeHHeM KaKoro-nu6yJJ.b rrpoBe)].ennoro na 3Tofr ¢urype mpe3Ka AB (puc.

B cBOIO otrepeJJ.b rroJio)KeHHe OTpesKa AB MO)KHO onpeJJ.eJIHTb, 3HaH KoopTOtrKH A u yroJI cp, KOTOpbiH OTpe3oK AB o6pagyeT c ocbiO x. Tol!KY A, Bbr6pannyiO )].JIH orrpeJJ.eJieHHH rroJIO)KeHmr q:mryphl S,

6y.n.eM B )].aJibHeiiweM Ha3biBaTb noAIOCOM.

T1pH JJ.BH)KeHHH ¢Hrypbr BeJIH'!HHbixA, YA u cp 6yJJ.yT H3MeHHTbCH. lJ.TOOhl 3HaTb 3aKOH )l.BHtKeHIUI, T. e. DOJ!O)KeHHe <\lHrypbi B DJ!OCKOCTU

127

Oxy B JIIoooil MOMeHr speMemi, Ha,n:o 3Harb saBHCHMOCTH

 

XA=fi(t), YA=fz(t), cp=fa(t).

(50)

YpasHeHHH (50), orrpe,n:eJIHIOill.He saKoH rrpoucxo,n:mn;ero L\BH>KeHHH, H33hiB3lOTCH ypaeHeHUH.MU 06Ua!CeHUH nAOCKOU rpucypbl B ee ITJIOCKOCTII. 0HH )Ke HBJIHIOTCH ypa6HeHUHJvtU nAOCKonapaA/leAbH020 06UJ/CeHUfl meepOOcJ meAa.

DepBb!e L(Ba H3 ypaBHeHlJii: (50) orrpe,n:eJIHIOT TO .lJ:Bll)KeH!Ie, KOTOpoe

qmrypa coBepwaJia 6bi

npn cp=const; 3TO, otJeBH.lJ:HO, 6y,n:er

rrocryrra-

y

TeJibHOe .lJ:BH)KCHHe, rrpH !WTOpOM

BCe TOtJ-

 

KH q:mrypb! ,n:BII)Kyrcn raK )Ke, KaK nomoc

 

A. Tperbe ypasnemre

orrpe,n:eJiner ,n:BII)Ke-

 

Hne, Koropoe qmrypa

cosepwaJia Obi rrpn

 

xA =canst H YA =const,

r. e. Kor,n:a rroJIIOC

 

A Heno,n:BIUKeH; aro 6yJI,er BPBili.eHHe 4m-

 

rypbr BoKpyr rroJIIOca

A. 0Tc10,n:a MO)KHO

 

33KJII01U!Tb, 'ITOB OOill.eM CJiytrae 06U:J/CeHUe

 

nAOCKoti rpucypbt a ee MOCKocmu .MO:J/Cem

 

pacc.Mampueambcfl KaK

CAaca/OU{eecH us no-

0'----------~x cmyname/lbHOco aeu:J/CeHUH, npu

Komopo.M

PHc. 143

ace mottKU rpuzypbt aauJJCymcH maK JJCe, KaK

noAIOC A, u us apaU{ameAbHOcO

oau:J/CeHUH

 

aoKpyc. amoc.o noAIOCa *.

 

0CH06Hbl.MU KUHe.MamutteCKU.MU xapaKmepucmUKa.MU paCCMaTpHBaeMOrO .ll:BH)KCHHH HBJIHIOTCH CKOpOCTb H ycKoperme rrocryrrareJibHOrO

.lJ:B~)KeHHH, paBHbie CKOpOCTH H ycrwpeHHIO ITOJIIOCa fvnocr=VA, a:0 CT= =aA), a raKme yrJioBaH cKopocrb ro H yrJioBoe ycKopemre e sparu:.a- reJibHOro .lJ:BH)KCHIIH BOKpyr ITOJIIOCa. 3Ha'!eHI1H3THX xapaKrepHCTHK B JIIOOOH MOMeHT BpeMeHl! t MO)KHO HaHn!, BOCITOJlb30B3BiliHCb ypaBHeHHHMH (50).

DpH usyqeHIIli ,JJ,BlliKeHHH MO>KHO B KatrecrBe ITOJIIOCa BblOHparb JIIOoyiO TOIIKY qmrypbi. PaccMOTpHM, qro ITO.JJyqllTCH, ecJIH BMecro A Bbl6parb B KaqecrBe ITOJIIOCa KaKyiO-HHDY.lJ:b ,n:pyry10 TO'-IKY C H orrpe,n:e- JIS'ITbITOJIO)KeiiHe cpurypbr orpesKOM CD, o6pasyiOIIJ.HM c OCbiO Ox yroJI cp1 (puc. 143). XapaKrepHCTHKII rrocrynareJibHOH qacrH .lJ:BH)KeHHH rrpu 3TOM H3MeHHTCH, TaK KaK B o6ru;eM cJiytrae Vc=FVA II ac=FaA (HHatre .lJ:BH-

)KeHHe

cpHrypbi

DbiJIO 6hr

rrocrynareJibHbiM). X apaKrepHCTHKH .JKe

Bparn.areJibHOH

'I3CTH.lJ:BH)KC!lllS'I,T. e. ffi H B, OCT3IOTC5l Helf3MCHHbL\1H,

B caMoM ,n:eJie,

rrpose,n:H H3

C rrpHMYIO CBr, rrapaJIJieJibHYIO AB, Mbi

BH.lJ:HM,

qro B JIIOoofi MoMeHr npeMeH!1 yroJI cp1 =cp-a, r,n:e a=const.

Orc10,n:a

~1=cp,

~1=~ IIJIH

cu 1 =w, £ 1 =e.

CJie,n:osareJibHO, 6paU{ame,lbHW1 1WCtnb aau:J/CeHUH om 6bt6opa noAIOCa He saaucum.

* CooTBeTCTBeHHo rrJiocKonapaJI,'lemo,Hoe .QBH)KeHHe TBep.Qoro TeJia MO)KHO pacCMarpHBaTb KaK c.ilaraJOm.eecH H3 nocTynareJibHoro ,1\BH)KeHJHI BMecre c noJIJOCOM A H Bpam.aTe.'lbHOfOBOKpyr OCH, nepneH.QHKYJillpHOH llJlOCKOCTH II (eM. pHC. 141) H npoxo- )l;lllll.eH '1epe3nomoc A .

128

§53*. OflPE,nEJIEHHE TPAEKTOPHA TOliEK OJIOCKOA $HfYPbl

DepeHiJ.eM Terrepb K ll3yqeHHIO iJ.BIDKeHHH OTiJ.e.llbHbiX T04eK ITJIOCKOH qmrypbl, T. e. K OTb!CKaHHIO TpaeKTOpHH, CKOpOcTeH H ycKOpeHHH 3THX TotreK. Ha4HeM c orrpeAeJieHHH rpaeKropuii.

PaccMorpHM TOtrKy M rrJiocKoii qmryphr, noJIO)KeHue Koropoii orrpeAe.rHrercH paccTOHHHeM b=AM or noJIIOca A H yrJIOM BAM =ex. (pnc. 144). EcJIH )l.BHllieHIIe 3a,IJ,aHo ypaBHeHHHMH (50), ro KOOp)J.HHaTbi x H y T04KH M B OCHX Oxy 6y,nyr:

x=xA +bcos (cp+cx.), y=yA +bsin (cp+cx.),

(51)

riJ.e xA, YA, cp- H3BeCTHbie no ypaBHeHHHM (50) ¢YHKUHH speMeHH t. PaBeHcrBa (51), onpe)l.eJIHIOU~He 3aKoH L\BHllieHHH T04KH M B rrJioc-

Kocru Oxy, )l.3IOT OL\HOBpeMeHHo ypaBHem1e rpaeKrop HH .3TOH TotrKH B rrapaMerputrecKOM BHL(e. Oob!'!Hoe ypaBHeHue rpaeKropmr rroJiytruM, HCKJI!04HB 113 CHCTeMbi (51) BpeMH t.

EcJIH paccMaTpusaercH L\BHllieHue 3BeHa KaKoro-HHDYL\h MexaHH3Ma, TO L(JIH onpeL(eJieHHH rpaeKTOpmr Jl!OOOH T04KH 3TOrO 3BeHa L(OCTaTO'IHO Bbipa3HTb ee KOOpiJ.HHaTbi trepe3 KaKOli-HHDYL\b rraparv!eTp, orrpeiJ.e.IIHIOIII,HH ITOJlO)KeHHe MeXaHH3Ma, a 33TeM HCKJII04HTb 3TOT napaMeTp. YpaBHeHH.H )l.BJ1)KeHu.n (50) nprr 3TOM 3HaTb He o6H3areJibHO.

PRe. 144 PRe. 145

3a}l.a'la 58. TioJJ3YHbl A R B, K KOTOpb!M npHKpenJJneTCR JlRRenKa 9JlJJRncorpa!pa, nepeMelll.a!OTCR no B3aRMHO nepneH,!(HKYJlRpHb!\1 HanpaBJJRIOIIl.RM (pnc. 145). PaccTOHHHe AB=l. Onpe,!(eJJRTb TpaeKTopmo TO'IKR M mmeilKR.

P e III e H 11 e. Bsas sa rromoc TO'IKYA, 6y.QeM onpe.QeJJHTb noJJOMeHRe TO'IKR M Ha mmefiKe oTpesKOM AM= b. OoJ!O}!{eHRe ca~10f1 JlRHeHKH 3all.aeTcH yrJJoM <p. Tor,!l,a

,!(JlH Koop,!(RilaT x R y TO'IKHM noJJy'IRM:x=(b-l) cos <p, y=b sin <p. HcKJJ!OlJaR napaMeTp <p, !IaXO)~RM, 4TO TpaeKTOpReH TO'IKR(H<~3aBRCRMO OT 3aKOHa ,!(BHJKeHR5! JlRHeHKR)

6y,!(eT 3JlJ!RTIC

x2/(b-[J2+y2fb2= 1

C TIOJlyOCHMR a= [b-ll R b R C UeHTpOM B TOlJKe 0.

MeHH5! C TIOMOlil.biO COOTBeTCTBy!Olli.RX BHHTOB paCCTOHHR5! [ R b, MOJKHO Bbi'lepTRTb KapaHJ(aiii0\1 M 3J1JJRnc c Jli06biMR 3aiJ.aHHhiMH noJJyocRMR, He npesocxoJJ.HW.HMR pasMepos JJHHeiiKR. OTC!O,!(a a Ha3BaHRe MexaHH3Ma - 9/l/luncocparp.

5 Jlf• 2173

129

Mo.n:yJih u HanpaBJieHHe
flOJIIOCa A;
d? ldt

§54. ORPE,IJ,EJIEHHE CJ(OPOCTEfl TOtJEI( RJIOCI(Ofl .HTYPbl

B § 52 obiJIO OTMe4eHo, 4TO )J:BRmeHHe rrJiocKoii qmryphr MO}KHO paccMaTpHBaTh KaK cJiararorn.eecH H3 noCTyrraTeJibHoro )J:BH.memm, npH

KOTopoM see T04KH qmryphr .U.BH}KyTca co cKopocTbiO vA nomoca A, 11 us Bparn.aTeJibHOrO )J:BH}KeHY!H BOKpyr 3TOf0 ITOJIIOca. f10Kax-<eM, 4TO CKO-

pOCTb JIIOooii T04KI1 M qmrypbi CKJia)J:biBaeTCH

reoMeTpH4ecKH

H3

CKOpOCTeH, KOTOpbre T04Ka noJiyqaey B Ka}KiJ.OM

!13 3THX ]J.BM}KeHr!H.

B caMOM .n:eJie, noJio}KeHHe JII06oii T04KH M qmryphl onpe.n:eJIHeTC.H no OTHOIIIeHHIO K OCHM 0xy pa.n:HyCOM-BeKTOpOM r t:_ +f' (puc. 146),

fAe rA - pa.n:uyc-BeKTOp flOJIIOca A' ? =AM - BeKTOp' orrpe.n:eJI.HIOlli.HM noJio}KeHHe TOtrKH M OTHOCHTeJibHO oceil Ax'y', nepeMemaromMxCH BMeCTe c rroJIIOCOM A nocTyrraTeJibHO (L\BHx-<eHue cp11ryphl no OTHoweHHIO K 3THM OC.HM rrpe)J:CTaBJI5!eT COOOH Bparn.eHHe BOKpyr flOJIIOca A). TorAa

-ctr drA ct?

VM=dt=dt+ctt•

B noJiyqeHHOM paseHCTBe seJIH4IIHa d~/dt vA ecTb cKopocTb BeJIH4HHa JKe pasHa Clmpocm v.MA• KOTOpyiO TOtiKa M

rroJiyqaeT npu rA =canst, T. e. OTHOCI!Te.'lbHOocei1 Ax'y', HJIH, HHatre rosopn, npu epawptuu tjJucypbt eoKpyc noA/Oca A. TarmM o6pa3oM, H3 npeiJ.biL\yruero paseHcTBa AeiicTBHTeJibHO c.rre)J:yeT, 4TO

(52)

T1pn 3TOM cKopocTb vMA, KOTopyro T04Ka M rroJiyqaeT npu sparueHHii cpurypbl BOKpyr ITOJIIOCa A, oy)J:eT (eM. §51):

VMA=W·MA (vMAj_MA),

(53)

r.n:e (!) - yrJIOBa.H CKOpOCTb qmrypbl.

TaKHM o6pa30M, c1wpocmb mo6ou mot~xu M nAocKou tjJuaypbt ceo-

.MemputieCKU CK/lGObt6aemCH U3 C1Wpocmu I'WIWU-Ht.t6yob apyzou nl04XU A'

Pnc. 146 Pnc. 147

npUHHmou sa noAIOC, u c1wpocmu, KOmopyw mottKa M noAytf.aem npa epaw,eHttU_ tjJucypbt BOKpyz amoco no.~wca.

CKOpOCTH VM HaXOA.HTCH flOCTpOeHHeM. COOTBeTCTBYIOill.ero napaJIJieJIOrpaMMa (puc. 147).

130

DapaJIJieJiorpaml, nocTpoel!Hhii! na Bernopax VMc HVc,

3a,n.a'la 59. Hal'ITHcKopocTh TOl!KH M o6o.r~a KOJieca, KaTllw:erocH no npliMOJIHHeiiHmly peJibCY 6e3 cK0.1h:lKeH!Ill (pHC, 148), eCJII{ CKOpOCTb UeHTpa C KOJieca paBRa vc. a yroJI DKM=ct.

P e III e H He. DpHHliB TO'lKYC, cKopoCTh KoTopoii H3BeCTHa, sa nomoc, Haii.r~e~l,

'IToVA1=Vc:+v,uc. r.r~e Vft1cj_CH H no ~Io)l;y.110 v111c=w·MC=wR (R- pa)l;Hyc Ko-

Jieca). 3nal!eHHe yrJioBoii cKopocTU w nafr)l;e\1 ns ycJIOBHll roro, lJTO TO'IKaK KoJieca He CKOJ!b3HT no peJihCy H, CJ!e)l;OBaTeJ!b!IO, B )l;3HIH>IH MO\IeHT BpeMel!H VK=O. C ,u;pyfOH cropoHhl, raK JKe KaK n l!Jill TOlJKH M, t7K=~+Vk-c. r.r~e vKc= w·KG= wR. TaK

KaK )];Jill TOlJKH K cKopocrH vKc n vc HanpaB.1eHhi B)l;OJ!h Ol\HOH npliMOi'!,To npH Vl(=O vKc=Vc, OTKy,u;a w=t'c R. B pe3)Jlhrare Haxo.u;HM, 'ITOvl\Ic=wR=vc.

6y.r~er npa 3TOM poM6o\l.

YroJI MeJK.!IY vc Hv,uc paBeH ~. TaK KaK cTopoHh!, o6pasyJOW:He aroT yroJI H yroJI B, ESaHMHO nepeneH,u;HKy.1HpHhl. B CBOJO o'lepe)l;hyroJI t\=2ct, KaK u.earpaJibHhlH yroJI, onnpaiOmal'lcllHa TY JKe ;ayry, 'ITOH BnJfcaHHhiH yroJI ct. Tor.r~a no CBOHCTBa~l poM6a

) r!lhl MeJK)l;y vc H 1!111 11 Me.-K::\Y VJ;c n VJI! To:lKe paBHhl a. OKOil'mTeJihHO, TaK KaK ,!(HaroHaJlH po"16a Bsa:nwo ne;,er.<eH;:(HKYJillpm>~, rroJJy'IHM

PacqeT, KaK BH,UH\1, oKa3hJBaercH .QocrarolJHO rpoM03.QKHM. B ,!(aJibHei:iiiieM 11hi TI03H3KOWI\ICH C ~1eTO,'J3~1H, ll03BOv1liJOW,m1ll peiiiaTb aH3.1J0f!{lJHh!e 33)1;3'111 ropa3,!(0 npow.e (eM. aa.r~a'ly 61 B §57).

§ 55. TEOPEMA 0 flPOEK~H51X CKOPOCTEfl

 

 

 

;:J.BYX TOliEK

TE.IJA

 

 

 

 

 

 

Onpe,n:eJieHHe

CKopoCTeii

TOtJeK

nJIOCKOH

4JHryphi (HJIH TeJia, ,ll,Bll-

)K)'Uieroc}J !1J10CKOITC!p<1lJJieJibllO)

C

ITOMO!IIbiO

cpOpMyJihi

(52)

CBH3aHO

OObi'!HO c ,n:oBOJlhHO c.'Ionmbi~m

pactreTaMH (eM. 3a,n:aqy

59).

O.n.HaKo

I!CXO,I\H H3 3TOf0 OCHOBHOfO De3y.'ILT3Ta,

 

 

 

MOlliHO ITOJiyqHTb pn,n: ,n:pymx, npaKTII-

 

 

 

'!eCKH6oJiee y,n:o6HL!X II rrpOCTb!X

MeTO-

 

 

 

.UOB orrpe,n:eJiemw

CKopocTeii: TotreK cpH-

 

 

 

ryphi (HJIH TeJia).

 

 

 

 

 

 

O,n:IIH H3 Tamrx MeTO.:!.OB

,n:aeT

Teo-

 

 

 

pow: npoeK"fUU CIWpocme(i OBljX fr10'1C:;;

 

 

 

mcep8oco me.tza I-ta ocb, npoxooHU{YtO <te-

PHc.

149

 

pe3 amu mo4Xll, pa'3rtbt apyc opy2y.

 

 

 

 

PaccMOTPII\! KaKlle-Hli6);IL ,lBe TO'lKHA H

B rr.'IOCKOilqmryphr (liJm

TCJra). DpHHHMaB ToqKy A sa no.1!DC (puc. 149), rro.'IytraeMnocpopMyJie (52), trTO vn=vA+vnA· 0Tcrc;:,a, npoeraHpyH o6e '!UCTH paBeHCTBa Ha ocb, Harrp2s.1emryro no AB, a Y'IliThiBMI,qTo BeKTop VnA neprreH,D.HKyJinpeH AB, Haxo,JJ..H:\1

(54)

H TCOpe11!3 ,I\CKD3a!la. 3a:'IIeTJ::\I, IJTO 3TOT pe3yJihT3T HCeH H Jl3 qHCTO Q":3ll'ICCKTIXCOOupm;<eHl!Y!: eCJIH paEe:'CTBO(54) He 6y,leT BbliTOm!SlTbCH, TO rrpn ,n:BmEeH!Il! poccronHHe Men..:!.y TOtrKaMH A I! B ,n:ommro II3l.reHnTLC5l, 'ITOHC'I:03\10iKHO,TDK K3K 1 CJlO C'liiTUCTC5Ia6COJII01 :m TBCp,n:bil\1.

Oo:YTOMY panencmo (54) BbiiTOJIJT<TClCH ne TOJihKO rrpa DJIOCKOrrapaJIJIC,lLHO~r, HO II rrpll JII060M ,ll.BlDi<CHIIH TBep,D.OfO TeJia,

S'

131

,UOK333HH35I Teope:vta IT03BOJHieT JierKO ll3XO,JJ,HTb CKOpOCTb ,JJ,aHHOH T04KH reJia, eCJIH l!SBCCTHbl HarrpaBJICHIIe CKOpOCTH 3TOH T04KH II CKO· pOCTb K3KOH·HHDYL\b ,JJ,pyrorr TOqKH TOrO )Ke TeJia.

3aJI.a'la60. HaiiTH 3aBHCIIMOCTb MeM.QY CK opoeTl!MII TolJeK A 11 B mmei1KII 3Jl-

JJHneorpa¢a (eM. p11e. 145) np11 )l;aiiHOM yn1e <p.

P e III e H H e. Hanpas"~eHHll eKopoereft TolJeK A 11 B 113BeeTHhl. Tor.Qa, npoeKTHPYll BeKTOphl VA 11 VB Ha oeb, HanpaBJieHHyiO no AB, noJJy'liiMcorJiaeHo ):\OKa3aHHOH

reope~1e

VA COS <p=VBeOS (90°-<p),

§ 56. OUPEAEJIEH HE CI(OPOCTEfl TOtfEK UJIOCKOfl $ HfYPhl C UOMOJ.UbiO MrHOBEHHOrO ~EHTPA CI(OPOCTEfl.

UOH51THE 0 ~EHTPOHAAX

.Upyroii rrpocroil II HarJI5I,JJ,llhiH MeroL( orrpe,JJ,eJieHH5I CKopocreii ToqeK l!JIOCKOH qmrypbl (HJIH reJia rrpH ITJIOCKOM ,JJ,Bll)KCHHH) OCHOBaH Ha ITOH5I· TllH 0 MrHOBeHHOM Ue!irpe CKOpOCTCH.

M mooeHHbt.M upmzpoM c1wpocmeil Ha3bt6aemcH mottiW nAocKoii if;ucy- pbt, c1wpocmb Komopoli 6 oaHHbtil MOMeHm 6peMeHU pMHa HYAIO.

JlerKO y6e,JJ,HTbC5l, qyo CCJIH 4Jnrypa ,JJ,BH)KeTC5I HCITOCTyrraTeJibHO, TO

T3K35I T04K3

B K3)K,Jl,blH MOMeHT EpeMCHH t CYlli.CCTBYeT H rrpHTOM CL(HH·

 

c rBeHHMI. flycTh B MoMeHr speMeHn t T04KH A

 

II B nJiocrwii: (jmrypLI

HMeiOT

cKopocnr

v:_ l1

 

VB,

He rrapaJIJieJibHh!e

L(pyr

,JJ,pyry

(pHc.

150).

 

Tor,JJ,a T04Ka P, JieJKalll.a5I

Ha

rrepeceqemm nep-

 

neHL(HKymrpoB Aa K BeKropy 0: u

Bb K

BeKTO·

 

py vB, H 6yL(eT MrHOBeHHh!M ueHrpoM crwpocreii,

P11c. 150

TaK KaK Vp =0*. B caMoM ,JJ,eJie, ecJIH L(orrycTHTb,

4TO Vp=#=O, TO ITO reopeMe

0

rrpoeKUH5IX CKOpO-

 

CTefi

BCKrop Vp ,JI,OJIJKell

ohiTb

O)J.HoBpeMemro

neprreH,JJ,HKYJI5IpeH H AP, (raK KaK vA..LAP) H BP (raK KaK VB iBP), 4TO HeB03MO.IKHO. J.-h TOH .IKC reopeMbl BIIL(HO, 4TO HHK3K35I L(pyra5I T04-

Ka ¢urypbl B 3TOT MOMeHT BpeMCHH He MO.tKeT HMeTb CKOpOCTh, paBHyiO HyJIIO (HarrpHMep, )J.JI5I TotrKH a rrpoeKurm vB Ha JIHHHIO Ba He pasHa HyJIIO H, CJieL(OBaTeJibHO, Va=fo0 II T. ,JJ,.).

EcJIH rerrepb B MOME'HTBpeMCHH t B35ITb T04KY p 33 ITOJIIOC, TO flO cpopMyJie (52) cKopocrL T04KH A 6yL\eT

raK KaK Vp=O. AHaJiorHtrHbiH pe3yJ1LTar rroJiytraercH )J.JIH JII06ofi L\PY· roi1 rotrKH ¢HrypLr. CJieL(oBareJibHO, cKopocmu motteK nAocKoii tjJuzypbt

onpeoeAHIOmCH 6 OaHHbtii MOMeHm epeJ>~eH.u maK, Kat\.. ecAu 6bt 06UaJCeHue ipucypbt 6bt/lo 6paU{eHueM 60Kpyc J.tcHoBeHHoco ~?eHmpa cKOpocmeil. flpu

* Pa3MCpbl qmryphl Beer,!(a MOMHO npe,!(eTaBHTb ee6e TaKIIMII, lJTO TO'lKap Oy)l,eT npHHa,!(.~e.lKaTb <>TOH qmrype (eM. HII)KC npiiMep II p11e. 151).

132