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vbi not^ifrc iiiiiabit, cxprimcrc forir.ulam portcrlorcm P cof. -1 

 -f-Q(iii. — vim tangcntialcm qua filum ia punclo Y follicira- 

 tur, alteram vcro formulam Pfin. — — Q cof. — vim norraalcna 

 eidem pun(flo applicatam, quarum crgo vtraque cx tenfionc T, 

 quam quidem pro lubiru fingcrc liccr, pcrfcdc dctcrminabitur. 

 Atque liinc pro ipfo fili initio E vbi j — o fiet 



P fin. ^ — Q cof. -^ z= i zz: — Q 

 idcoque Q=: — — • Similiquc modo 



P cof -^ -F Q fin. -L i:^ — T' z= P. 



§. 24. His formulis euolutis ponamus vim fangentia- 

 Jcm acccler.itriccm fccundnm dircdionem Y/ agcntem : — Q, 

 at vim normaicm fccundnin dircdionem Y O vcrfus ccntrum cir- 

 culi tendcntcm — 11, ita vt fit 



== P cof. -i- -h Q fin. -'- et 



n = Q cof -i- — P fin. i- 



^ r r 



atque valorcs harum dnarum virium erunt 

 — — T" -j- ':- fin. -1 — 1:2 et 



n =:—.'• -f- ^- " cof. -L — !l' -h z1j:'JJ., 



r VLg r •i.g »gr» 



Nunc ii;i:ur cum quacltio in fe fit indctcrminata, fcqucntia Pro- 

 blcmara fpccialia pcrcnrrainus, in quibus ratio viriuin foUicitan- 

 tium pracfcribitur, vt filo motus fupra allignatus inducatur. 



Problcma I. 



§. 25. Drfinire vires tangetitialcs ad motum fupra de- 

 fcyiptum m Jilo prodiu-ciidum rcquifitas. 



Solutio. 



Cum igitur liic folac vircs tangentialcs rcqufrantur, rf* 

 rcs normaics II cuanefctnt ita vt fit 11 Ziz o , vnde cx poflrc- 



P 2 ina 



