PY241 Solutions Set 6 (Dated: October 21, 2002) 6-9 The force on ...

m¬©V¢¡¤£ —¥¦¬©X2”Z¨©©£ª ªª ª¦¥¦ › —‚V¯W¾¡:œU ¡ › —‚V¯WÑœ X”i¨©k W”2l¨ X©X”i¨©¢¡¤£¦¥¨§©©#"%$&('*),+-.$/102&.354761841919:41;!@ABDCFEHG(IJBDEHKML7KNEHOPB1I?QRTS#UVẄ XZY,[2\#AB%G.B]X^R_S#La`bEcSdReQ.RgfcB]IJEHKhSQ(L7KiQ1jk LilmQ\#A*LnQ#o_E2I%LnQ.RgEcK^RTSQ.ABpEHO2PBqI?Q#R_KNBqrisRgo_R_OGdR_stvuU‚V‚Ẅ XZYƒ\#R_ogo„OhB~|%B1GdE…RTSxLnQMY}V‡†jmKwEHO2PBqI?QxR_SMR_KwB1risR_ogR_OG.RgstyReCaQdABzCFEcG.I%B{RTSM|%B1GdEhj}@AB~EHK*og€`*o_LcIJBz\#AB%G.Bk †ilˆVẄ X k †cl¦V‰†Uk OblŠ¨SdRgK‹ŒR_KiQdB1‹HG(LnQdR_EHK [i\#AhLnQRTSQdABp\EHG.Žv2EHK*BpOi^U\#AB1K‘Q.ABpEHOPB1I?Qt’EnfcB1S5CFGdEct“YNVW”’QdEŒY^V‰†cu•{EcGdŽvRTS#2B%–*KB1MLcS—‚V¤˜š1› Upž YŸĵ Š¨SdRgK‹ŒUVẄ X2Yz:œƒẄ X2YhžcYXZYb¨— V§W©«ª¥¦X k †cl¨— V§WW k WlˆVk¬ lk Iql­En\¤t„s*I(AM\EHG.ŽŒR_S#2EcKBpOZ‘U®\#AB%KML7KMEHOPB1I?Q#t’EnfHBqS5CFGdEct“YNV¯W”’QdE’YNV€”Zu•{B]I1L7KNs*SBDQ.AB]S.L7t’BDRgKiQdB1‹HG(L7oLHSObBJCFEcGdBc[:Ps*SQ\#ReQ.A¢2Re°±B%G.B%KiQ#o_Rgt’RgQ.S1j— V²WXZYh¨©«ª— V²WW k Wk © llˆV‰†

U ¡ 1› VWÑœ •{B]I1L7KÀPs*SQshSB]I%EHK*SdB%G.fnLnQdR_EHK^E7CŸB%KB1Gd‹cŒQdEŒSdEHo_fHBºQdARTS#`G.EHO*ogB1tN¬¨R_KN\BpI%LHKNSdEHo_fHBºCFEHG¤¬¬©©¸¬© — Vy^µ ¨¸¸¬©¬©¸V‘µ ¨Vyµ ¨Vµ©¸Vl¸£¸¸V^µ ¨ x· ¥ ¨©RTSQdA*B]L:fHB%G(L7‹cB#CFEHG(IJBcjš•{EcGdŽvtÀs*SQB1ris*L7o±Q.AB]I(A*LHK‹HBDR_K^ŽZR_KBJQ.R_IDB1KB%G.‹H± ˆ—‚V‰¼¾½¡ DWz¼{½£¢U •AB%G.B‰Ñž Y¼¾½¤ pWz¼{½£¢~V‚—© †Ád†c†H†vÇÈV²W Ñ U ¡†DWžHYk¨§ l†Ád†c†H†ÀÂ}Ì1 V Ñ U k¬ xlW¦¥©UV © †Á.†H†c†H Ñ

¬© z¬ †£¢ÀÇ ÃXiµ¬©Xiµ {¬ † ¢ 马© `hB1G¢Sdris*LHGdBzt’BJQ.B%GxE7CÀQdAB~BqL7GdQdA7 SMSsGdCÄLHI%BH[DL:fHB1G.LH‹HR_K‹¤EnfHB1GMo_L7QdRgQds*2B½IH ¢KJ£LºV k( † © lšÌ k¬ z¬ † ¸ ¢ —lV Ã Ò {¬ † ¸ M — k¬qÒ l@ABpG.L7QdR_EÀEHCŸ\#R_K*NB%K*B%G.‹H’QdE’Q.E7Q(L7o`bEn\5B1GshSBq^OZvAZstŒLHK*SR_S#QdAZs*S1Ò {¬ † ¸ M — ÃÃObl’¹*LnQ‘Sds``*ogR_B1S à ¡ …¬ †£¢{ǤEHCºB1KB%G.‹H `bB%G‘ŽiR_o_EH‹HG(L7tM[ˆ\#A*R_I(A…R_S‘IJEHKZfcB%GdQdB1¤QdE~t’B1I(A*LHKRTI%L7o#B1KB%G.‹H \#RgQdA€L © †¾`bB%G(IJB1KcQk­¨En\‰t„shI(A‘CÄL7Q\#Rgo_oQdA*B]2RgB%QdB1G#s*SBps*`huB¥¤vI%RgB1K*IJvG(LnQ.BHĵ¦ÉBJQdQdR_K‹¨§OhBDQ.ABpKZst„ObB%G#EHCŸŽZR_ogEc‹HG(L7tŒSEHC,CÄL7Qs*SdB1^s`Ék § Xiµl ©zk( © †l¤VÍ Á.†H†c†ŒÇV § ÍiÒ {¬ † ¥ XZµ k¬H¬ l§ V kFÍ Ád†c†H†ŒÇ l ©Ç

@AR_St’LHŽHBqSQ.ABpG(LnQdR_E’E7CŸ\#RgK*NB1KB%G.‹HŒQ.E’s*SBqNB%KB1Gd‹cbz¬ † ¸ ]— ¬_¬2¬ j Í [‘\B‰I%LHKÊogEZEcŽ®s`“QdABwLHI%I%B%o_B%G(LnQ.RgEcK 2RTSQ.L7KhIJB‰ž L7K* A*B%R_‹HAiQ “CFEHG ObE7Q.A“LŽnL7K‹iL7G.EZĒ L7K*ÊLo_E¢¡¹G.EHt§Q.L7O*ogBIJshSQq£VŒžÀV ¬ †a Á¤‘V © „¼{”9±µ2”¤£¦¥¦¥„’žaV † à Á£‘V à §¨¥©±·5—VV——žÒ © µ † Ã Ò © k l k( à l à © Í ÇÉXZµ ¥É¸ Æ © Ò · V† ¬Ò © k l k © 7l © § Ç Xiµ ¥¸ ç© Ò · ££LÍk † à l kÓÃ Ò {¬ † ¸ M —lˆV ¬ g¬, z¬ † ¸ — k¬ Hl¬ † ¸ à —V ¬ † Í k¬ là 8EHC,Q.ABDQdEHQ.L7o\#R_K*NB%K*B%G.‹HvRTS#SQ.Rgo_o ¬ †„Q.Rgt’BqSQdAB]LHt’EHsKiQ#AZstŒL7K*Ss*SdBHjb´L7oTIJsoTLnQ.BQ.ABp\EHG.ŽvL7K*N`bEn\5B1G`bB%G#s*KReQt’LcSdSR_KÀPst’`RgK*‹ŒCFEHGLaŽnL7K‹iL7G.EZEÀL7KhNLao_E2IJs*SQ1j5‘B%KB1Gd‹c‘IJEcK*SB1GdfnL7QdR_EHKÉ[iQdA*BDQdE7Q(L7o\EHG.Žv2EHK*Bpt„s*SQ#OhBpBqrcshL7oQ.EÀQ.ABpB%K*B%G.‹HvLnQ#Q.ABp`bB1L7Ž‘E7CŸQdABPst’`Éj— V€½ < @¦V ^µ ^µZžaV ^µ k žil k¬ l@ABp\5EcGdŽŒ`bB%G#s*KReQt’LcSdSRTSQdA*B%G.BJCFEHG.BHVµ k žZl k © †ilm``o_ZRgK*‹’QdARTSQdEaQ.ABDQ\5EŒI1LHSdB1S\5BpAhL:fHBH¼¾”G±µZ”¤£¦¥¦¥ÀVµ k © ¬ †clV ç © § Ç Xiµ ¥É¸ k © ¬ l§¥©·Vµ k( à † à lV à à © Í Ç Xiµ ¥É¸ k ©H© lEa‹HB%QQdA*Bº`bEn\B%Gq[c\BK*B%B1vQdEaŽZKEn\AEn\o_EHK‹aReQQ.LHŽHBqŜ Q.Ë Pst’`^QdABDLHI1IJB1ogB1G.L7QdR_EHK‘2RTSQ.L7KhIJBžhĵ @R_taBºRTSR_SQ.LHK*IJBD2R_fiRT2Bq@SEM\B’KB%Bq¾Q.EMŽiK*En\®L7K~L:fHB1G.LH‹HBÀfHB%o_E2IJRgQ¾2sG.R_K‹NQdABºPst’` R_KzEcG.B%GºQdExSdEHo_fHBaCFEHGDQ.Rgt’BHj¨B%‹cogBqI?QdR_K‹xžh[ÉQdA*R_SOZ¢fHB1ogE2I%ReQc[fHB1ogE2I%ReQxRTS5Ps*SQ Ò ¿ Ò¤ © µÉjÀ­¨En\®2EN\5B’‹cBJQºQdARTS.uwŠSR_K‹NB%KB1Gd‹c¢IJEHKhSB1GdfnLnQ.RgEcKÉ[±\5BŒI1L7K¾‹cBJQD¿[ÉQdAB’R_KReQ.R_LHo¦fHB1ogE2IJRgQHjm¨S.Sdst’RgK‹’Q.A*LnQ#Q.ABpfHB1ogE2I%ReQ‘L7QQdAB]`bB1LHŽvE7CŸQdA*BPst’`xR_S|1B%G.E*[ZQdA*B]L:fHB%G(L7‹cB¨RTSšPs*SQ Ò*k ¿ ¢ ¿ lV Ò ¿ĵ Š¨SdR_K‹¦V[\B‹HB%QQdABPst’`R_K‹ŒQ.Rgt’BDCFEcGQdABpŽnL7K*‹cL7G.EZEÀLHK*vQ.ABpo_EZI%s*SQ1 M¼{”9±µ2”¤£¦¥¦¥„ ¢VV © Ò · k © à l§¥©· ¢VV † © Ò · k © Í l#¨R_fZR_2R_K‹aQdA*B\EHG.Ž’`hB1Gs*KReQ#tŒLHS.S5CFEHsKh‘R_KvQ.ABº–*G.SQ`*L7GdQEHCÉQdA*Bº`*GdEcOogB1tÊOZ’QdAB5Pst’`R_K‹aQdR_taBD‹cRgfcB1S5s*S5QdABD`bEn\5B1G5`bB%GsKRgQtŒLHS.S%—¬V¼¾”G±µZ”¤£¦¥¦¥À V ¬qà © Ç Xiµ ¥É¸ k © Ò l§¨¥©±·5V ¬1Ã*¬ Ç Xiµ ¥¸ k © § l

¦¦¬©¦'¦¦¬©¨ N¿£¦¦¦¢V¿Z¨© µ £¦Vx· ¥É¸ l¨ kÓÒk x· ¥ ¨ l ©¦¸¦¦¦Ä¨¢ ¦¦¦ÒQ.A*LnQ RgC‘QdA*BG.L7QdB LnQ~\#AR_I(A E:Å2Z‹HB%K R_S LHO*SEcGdObB1¯Oi®L7K®LHKR_t’LHoŒL7K* Ss*``o_RgBq¯Q.EwRgQ.SzQ.R_S.SdsB1SzfnL7G.RgBqS~LHS{QdABZAEn\¥É¸ jD•A*LnQp2EZB1S¨QdA*R_SDSds‹H‹cB1SQL7ObEHs2QSdsGCÄLcIJBaL7G.B1LŒEHC¦QdAB’L7GdQdB1GdR_B1S1[*Q.AB%K{ReQ(S¨`bEn\B%GºEHs2Q.`s2QD`hB1GsK*ReQDtŒLHS.SSdAEHs*o_xfnLHGdxLHS¡QdA*Bp`soTSBpG(LnQ.Bqu\#ARTI(A“E:Å2Z‹HB%K RTS LHO*SEcGdObB1 R_KiQdEQ.ABwOogEZE2SQdG.B1LHt²RTS2R_G.B1I?Q.og `G.EH`bEHGdQdR_EHK*LHoŒQdE QdABm¨S.Sst’R_K‹¯Q.A*LnQQdAB¤G.L7QdB‰L7Q`bEn\5B1GEcs2Qd`*s2Q1[h\5Bp2R_fZR_2BpOZŒQ.ABptŒLHS.SQdE’‹HB%Q#QdABp`bEn\B%GEHs2Q.`s2Q`bB%Gs*KReQtŒLcSdS1j£¢¥¤ ¨ ”§¦%·¥ £¨¦ ¥A £n”¤ ¨ ”§¦%·¥ £¨¦ ¥A £n” ¤k © Hl ¢»DKEn\#RgK*‹ÀÄḦ[\5BpI1L7KMSB1BºA*En\€QdA*Bp`hEn\B%G#`bB%G#tŒLHS.S#S.I%L7o_B1S1j¢ LHK* ¤ ¨ ”©¦J· ¥ £¨¦ ¥A £n”¤ ¥É¸k © l¢¨ ”©¦J· ¥ £¨¦ ¥A £n”¤ ¢¤

@ABpfHB1ogE2IJRgQŒE7CŸQdA*Bp\L7QdB%GRTS#KB1‹cLnQ.RgfcBºSdR_K*IJBpRgQR_S¡ hEn\#RgK‹Œ2En\#KZ\L7G(S5\#ARgo_BDQdA*B]SdLHogt’EHKNRTS#S\#R_t’taR_K‹Œs`Z\L7G(S1j¦¬©¨ N¿£m‹cLHRgKN\BDI1L7KMs*SdBDB%KB1Gd‹cvIJEHKhSB1GdfnLnQ.RgEcKÉj¬©V£µ¬©¨££¦V¬©¨ ^¿£§k IqlvÎÏC„QdAB{CÄL7o_o_S^RTS © tARg‹cAÉ[¨\#AhLnQ^RTS^QdABzt’RgK*RgtÀst‡AB%R_‹HAiQ^QdE…\#AR_I(A€QdAB{–hSdA‰t„shSQÀPst’`¤R_K‰EcG.2B1GvQ.ESd\#Rgt‡s`‰QdABG.B1SQEHC,Q.ABp\L:2um‹cLHRgKN\#G.ReQ.RgK‹Œ2En\#KM½ V½ ¢^µ) )K+V ‘µ£¢ < kÓÃHà l•AB%G.B £¢