Recitation 16 1 2 Antiparallel Newton's 3rd law Summary: two ...

2I[XSR W VH PE[
%RXMTEVEPPIP
6IGMXEXMSR
7YQQEV] X[S HM IVIRX VMKLX LERH VYPIW [IVI YWIH XS RH XLI HMVIGXMSRW SJ XLI
QEKRIXMG JSVGIW ;MVIW GEVV]MRK GYVVIRXW MR STTSWMXI HMVIGXMSRW VITIP IEGL SXLIV
ERH [MVIW GEVV]MRK GYVVIRXW MR XLI WEQI HMVIGXMSR EXXVEGX IEGL SXLIV

*SYV PSRK WXVEMKLX [MVIW GEVV] IUYEP GYVVIRXW MR XLI TEKI EW WLS[R 8LI
QEKRIXMG JSVGI I\IVXIH SR [MVI * MW
% RSVXL
& IEWX
' WSYXL
( [IWX
) ^IVS
-J XLI TVSFPIQ LEH EWOIH JSV XLI QEKRIXMG IPH XLIR MX [SYPH LEZI TSMRXIH 2SVXL
EW WLS[R FIPS[

8LI HMEKVEQ WLS[W XLVII IUYEPP] WTEGIH [MVIW XLEX EVI TIVTIRHMGYPEV XS XLI
TEKI 8LI GYVVIRXW EVI EPP IUYEP X[S FIMRK SYX SJ XLI TEKI ERH SRI FIMRK
MRXS XLI TEKI 6ERO XLI [MVIW EGGSVHMRK XS XLI QEKRMXYHIW SJ XLI QEKRIXMG
JSVGIW SR XLIQ JVSQ PIEWX XS KVIEXIWX
%
& ERH XMI
' ERH XMI XLIR
( ERH XMI XLIR
)
QMRMQYQ
JSVGI

%QTIVI W 0E[
1E\[IPP W )UYEXMSRW
4EXL MRXIKVEP ERH HM IVIRX WYVJEGIW
'SQTEVI ERH GSRXVEWX +EYWW 0E[
8LMW TEVXMGYPEV %QTIVMER PSST
LEW ER SVMIRXEXMSR SYX SJ XLI
TEKI WS GYVVIRXW GSQMRK SYX
SJ XLI TEKI EVI TSWMXMZI ERH
GYVVIRXW KSMRK MRXS XLI TEKI
EVI RIKEXMZI
6IQIQFIV XLEX ER %QTIVMER PSST MW NYWX E PSST MR WTEGI MX MW WSQIXLMRK [I QEOI YT
ERH WLSYPH RSX FI GSRJYWIH [MXL E GYVVIRX GEVV]MRK PSST
%QTIVI W 0E[ MW ZIV] WMQMPEV XS +EYWW 0E[ ERH EPWS PIEHW XS XLVII X]TIW SJ I\EQ UYIWXMSRW

'VSWW WIGXMSREP ZMI[
RYQFIV
SJ PSSTW
7SPIRSMH )\EQTPI
PIRKXL SJ
WSPIRSMH
GYVVIRX S[MRK
XLVSYKL IEGL PSST
4WIYHS ( ZMI[
QEKRIXMG IPH
MRWMHI E WSPIRSMH
;%62-2+ (SR X QM\ YT XLI GYVVIRX HIRWMX] R ! 2 0 [MXL XLI RYQFIV SJ GYVVIRX
PSSTW 2

-R %QT´VI W 0E[ XLI MRXIKVEXMSR QYWX FI SZIV ER]
% WYVJEGI
& GPSWIH WYVJEGI
' TEXL
( GPSWIH TEXL
) GPSWIH TEXL XLEX WYVVSYRHW EPP XLI GYVVIRX TVSHYGMRK &
=SY GER WII MR XLI I\EQTPI SJ XLI WSPIRSMH XLEX [I HMHR X RIIH XS
WYVVSYRH EPP SJ XLI GYVVIRX TVSHYGMRK & MR SVHIV XS ETTP] %QTIVI W
0E[

8[S PSRK WXVEMKLX [MVIW IRXIV E VSSQ XLVSYKL E [MRHS[ 3RI GEVVMIW E
GYVVIRX SJ % MRXS XLI VSSQ [LMPI XLI SXLIV GEVVMIW E GYVVIRX SJ %
SYX 8LI QEKRMXYHI MR 8zQ SJ XLI TEXL MRXIKVEP MR %QTIVI W 0E[ EVSYRH XLI
[MRHS[ JVEQI MW
% ö £
& ö £
' ö £
( ö £
) RSRI SJ XLIWI
[LIVI XLI TEXL ' MW XLI
[MRHS[ JVEQI
I 8 Q

% PSRK WXVEMKLX [MVI VEHMYW 6 ! QQ GEVVMIW E GSRWXERX GYVVIRX
HMWXVMFYXIH YRMJSVQP] SZIV E GVSWW WIGXMSR TIVTIRHMGYPEV XS XLI E\MW SJ XLI
[MVI -J XLI GYVVIRX HIRWMX] MW . ! % Q MR XLI ^ HMVIGXMSR [LEX MW XLI
QEKRMXYHI ERH HMVIGXMSR SJ XLI QEKRIXMG IPH & EX XLI TSMRX 4 PSGEXIH
QQ JVSQ XLI E\MW SJ XLI [MVI EPSRK XLI \ E\MW# 2SXI XLEX XLI ^ E\MW
TSMRXW SYX SJ XLI TEKI
4
MRXS XLI TEKI

8LI KVETL XLEX FIWX VITVIWIRXW & EW E JYRGXMSR SJ V JSV E [MVI SJ VEHMYW 6
GEVV]MRK E GYVVIRX - YRMJSVQP] HMWXVMFYXIH SZIV MXW GVSWW WIGXMSREP EVIE MW

8[S PSRK WSPIRSMHW VEHMM QQ ERH QQ VIWTIGXMZIP] GEVV] XLI WEQI
GYVVIRX - ERH S[ MR STTSWMXI HMVIGXMSR 8LI WQEPPIV WSPIRSMH MW QSYRXIH
MRWMHI XLI PEVKIV EPSRK E GSQQSR E\MW -X MW SFWIVZIH XLEX XLIVI MW E ^IVS
QEKRIXMG IPH [MXLMR XLI MRRIV WSPIRSMH 8LIVIJSVI XLI MRRIV WSPIRSMH QYWX
LEZI < XMQIW EW QER] XYVRW TIV YRMX PIRKXL EW XLI SYXIV WSPIRSMH [LIVI <
MW
'VSWW WIGXMSREP ZMI[

8[S ZIV] PSRK GSE\MEP G]PMRHVMGEP GSRHYGXSVW EVI WLS[R MR GVSWW WIGXMSR
FIPS[ 8LI MRRIV G]PMRHIV LEW VEHMYW E ! GQ ERH GEVVMIW E XSXEP GYVVIRX SJ
- ! % MR XLI TSWXMZI ^ HMVIGXMSR TSMRXMRK SYX SJ XLI TEKI 8LI SYXIV
G]PMRHIV LEW ER MRRIV VEHMYW F ! GQ SYXIV VEHMYW G ! GQ ERH GEVVMIW E
GYVVIRX SJ - ! % MR XLI RIKEXMZI ^ HMVIGXMSR TSMRXMRK MRXS XLI TEKI
=SY QE] EWWYQI XLEX XLI GYVVIRX MW YRMJSVQP] HMWXVMFYXIH SZIV XLI
GVSWW WIGXMSREP EVIE SJ XLI GSRHYGXSVW ;LEX EVI XLI QEKRMXYHI ERH
HMVIGXMSR SJ XLI QEKRIXMG -IPH & EX TSMRX 4 [LMGL PMIW SR XLI ] E\MW EX
] ! GQ#
4
% 8
& ö £ 8 MR XLI RIKEXMZI \ HMVIGXMSR
' ö £ 8 MR XLI TSWMXMZI \ HMVIGXMSR
( ö £ 8 MR XLI RIKEXMZI \ HMVIGXMSR
) ö £ 8 MR XLI TSWMXMZI \ HMVIGXMSR