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Lh]^Z ξ = A cos (ω 0 t + ϕ 0 ) ; ω 0 =– djm]h\Zy pbdebq_kdZy qZklhlZ kh[klm\_gguodhe_[Zgbckbkl_fu ξ(0) = Acosϕ0, lh_klv ϕ0 – gZqZevgZynZaZdhe_[Zgbc ϕ = ω0t +ϕ0 – nZaZdhe_[ZgbcIhZgZeh]bbk\jZsZl_evguf^\b`_gb_fν = 2πω 0 – qZklhlZdhe_[Zgbc2πT=– i_jbh^ dhe_[Zgbc A = ξmax – Zfieblm^Z dhω0e_[Zgbc QZklhlZ dhe_[Zgbc ]Zjfhgbq_kdh]h hkpbeeylhjZg_aZ\bkblhlZfieblm^u (dhe_[Zgbybahojhfgu).JZkkfhljbf f_oZgbq_kdmx b we_dljbq_kdmx fh^_eb ]Zjfhgbq_kdh]h hkpbeeylhjZ >ey f_oZgbq_kdh]h<<<<hkpbeeylhjZ m ξ = − kξ , ]^_k±dhwnnbpb_glmijm]hklbξ = A cos (ω 0t + ϕ 0 ) ; W = U + T =ijm`bgu Lh]^Z<2kξ 2 m ξkA2=+=.
>ey we_dljbq_kdh]h dhglmjZ2224q= 0, ]^_q – aZjy^gZdhg^_gkZlhj_L – bg^mdlb\ghklvdZlmrdbK±zfdhklvdhg^_gC1q 2 LI 2 q02;W=. LZdbfh[jZahfkms_kl\mkZlhjZLh]^Z q = q0 cos (ω 0t + ϕ 0 ) ; ω 0 =+=2C22CLC_lZgZeh]byf_`^mf_oZgbq_kdbfbbwe_dljbq_kdbfbdhe_[ZgbyfbL – ZgZeh]m, 1/C – ZgZeh]k.<<L q+<NZah\h_ijhkljZgkl\h±ijhkljZgkl\hgZlygmlh_gZ\_dlhjZ ξ , ξ . <kemqZ_]Zjfhgbq_kdh]h hkpbeeylhjZ djb\Zy ij_^klZ\eyxsZy dhe_[Zgby \ wlhf ijhkljZgkl\_ bf__l \b^ weξ2ξ2ebikZ 2 + 2 2 = 1 . A A ω0<4) Ijbf_jubkihevah\Zgbyfh^_eb]Zjfhgbq_kdh]hhkpbeeylhjZ:JZkkfhljbf ^\Z l_eZ jZaghc fZkku kh_^bgzggu_ ijm`bghc k `zkldhklvx k (wlZ kbkl_fZ k\yaZgguohkpbeeylhjh\fh^_ebjm_l\Ze_glgu_dhe_[ZgbyZlhfh\\^\moZlhfghcfhe_dme_ m1 ξ1 = − k (ξ1 − ξ2 ) ; m1ξ1 = − m2ξ2 p_gljfZkkfhe_dmeu^he`_g hklZ\Zlvky g_ih^\b`guf ihkdhevdm \g_rgb_ kbeu hlkmlkl\mxl Lh]^Zmmkµ ξ1 = −kξ1 , ]^_µ = 1 2 – ijb\_^zggZy fZkkZ QZklhlZ kh[kl\_gguo dhe_[Zgbc ω 0 =,µm1 + m2lh _klv gZ[ex^Z_lky ihegZy ZgZeh]by k fh^_evx f_oZgbq_kdh]h hkpbeeylhjZ i ?kebkfZkkZh^gh]hbal_eklj_fblkydgmexlh µ → m1 ; ω 0 →.m15) :g]Zjfhgbafdhe_[Zgbc:<fh^_eb]Zjfhgbq_kdh]hhkpbeeylhjZF = – kξ, lh_klvFebg_cgZh^gZdh_keb[jZlvba jZaeh`_gby nmgdpbb U \ jy^ L_cehjZ i qe_gu [he__ \ukhdh]h ihjy^dZ lh<<<<<<F = − kξ − k1ξ 2 + ...
= f (ξ ) ⇒ m ξ = f (ξ ). <wlhfkemqZ_dhe_[Zgbyg_ebg_cgu (j_r_gb_fy\ey_lkyi_jbh^bq_kdZyghg_]Zjfhgbq_kdZynmgdpbydhlhjZyh^gZdhfh`_l[ulvijb[eb`_gZkmffhc]Zjfhgbq_kdbojZaeh`_gb_f\jy^Nmjv_hgbg_bahojhfguqZklhlZaZ\bkblhlZfieblm^u ihkdhevdm kbkl_fZ bf__l g_kdhevdh kh[kl\_gguo qZklhl fh^u dhe_[Zgbc i_j_klZxl[ulvg_aZ\bkbfufbkf K\h[h^gu_ dhe_[Zgby kbkl_fu k\yaZgguo hkpbeeylhjh\ GhjfZevgu_ dhe_[Zgby fh^u QZklhlu ghjfZevguo fh^ ^ey kbkl_fu khklhys_c ba ^\mo hkpbeeylhjh\f_oZgbq_kdbo b we_dljbq_kdbo H[sbc f_lh^ hij_^_e_gby ghjfZevguo fh^ b ghjfZevguodhhj^bgZl1) GhjfZevgu_fh^ubghjfZevgu_dhhj^bgZlu:GhjfZevgu_dhhj^bgZlu±dhhj^bgZlu\\_^_gb_dhlhjuoiha\hey_lk\_klbmjZ\g_gby^\b`_gby kbkl_fu k\yaZgguo l_e d kbkl_f_ ebg_cguo ^bnn_j_gpbZevguo mjZ\g_gbc k ihklhyggufbdhwnnbpb_glZfbdZ`^h_badhlhjuokh^_j`bllhevdhh^gmi_j_f_ggmx±h^gmbaghjfZevguodhhj^bgZlQbkehghjfZevguodhhj^bgZljZ\ghqbkemkl_i_g_ck\h[h^ukbkl_fulh_klvqbkemmjZ\g_gbcdhlhjufbhibku\Z_lkykbkl_fZGhjfZevgu_ fh^u ± dhe_[Zgby hibku\Z_fu_ mjZ\g_gbyfb gZ ghjfZevgu_ dhhj^bgZlufh]ml[ulv\ha[m`^_gug_aZ\bkbfh^jm]hl^jm]Zg_h[f_gb\Zxlkywg_j]b_c52) F_oZgbq_kdb_hkpbeeylhju:JZkkfhljbf ^\Z ]jmaZ h^bgZdh\hcfZkkuk\yaZggu_ijm`bghc`zkldhklb k1 ]jmau k\yaZgu k g_ih^\b`gufb hihjZfb ijm`bgZfb `zkldhklbm ξ = − kξ − k ξ − ξm ξ = − kξ11( 12) I 1I, ]^_ξI = ξ1k.
Lh]^Z keh`bfb\uql_fmjZ\g_gby m ξ 2 = − kξ 2 + k1 (ξ1 − ξ 2 )m ξ II − ( k + 2k1 )ξ II+ ξ2; ξII = ξ1 – ξ2±ghjfZevgu_dhhj^bgZluJ_r_gb_fkbkl_fu y\ey_lky gZ[hj ]Zjfhgbq_ξ I = AI cos (ω I t + ϕ I )k + 2k1k, ]^_ ω I =, ω II = ± qZklhlu ghjkdbo nmgdpbc ξI b ξII: mmξ 2 = AII cos (ω II t + ϕ II )ξ + ξ IIξ − ξ II; ξ2 = I. LZdbfh[jZahf^eyfZevguofh^kh[kl\_ggu_qZklhlukbkl_fu ξ1 = I22gZoh`^_gby \k_o iZjZf_ljh\ dhe_[Zgbc kbkl_fu g_h[oh^bfh q_luj_ gZqZevguo mkeh\bydhlhju_iha\heylhij_^_eblv:I, AII, ϕI, ϕII.?keb\gZqZevgucfhf_gl\j_f_gbkhh[sblv]jmaZfh^bgZdh\u_ihfh^mexbgZijZ\e_gbxkf_s_gbylh ξII = 0. Lh]^Z[m^_l\ha[m`^_gZlhevdhgbadhqZklhlgZyfh^Zdhe_[Zgbc]jmau dhe_[exlky dZd _^bgh_ l_eh ?keb khh[sblv ]jmaZf h^bgZdh\u_ ih fh^mex gh jZaebqgu_ihgZijZ\e_gbxkf_s_gbylhξI = 0; \ha[m`^Z_lky\ukhdhqZklhlgZyfh^Zdhe_[ZgbcIjbwlhf\h[hbokemqZyooZjZdl_jdhe_[Zgbcg_baf_gy_lkykh\j_f_g_flh_klv\lhjZyfh^Zg_ \ha[m`^Z_lky ± g_ ijhbkoh^bl h[f_gZ wg_j]b_c f_`^m fh^Zfb Ihwlhfm ghjfZevgu_fh^u y\eyxlky g_aZ\bkbfufb ?keb k\yav f_`^m ]jmaZfb ± keZ[Zy ( k1 k ) , lh qZklhlughjfZevguofh^[ebadbgZeh`_gb_^\modhe_[Zgbck[ebadbfbqZklhlZfbijb\h^bldf_^e_gghfmbaf_g_gbxZfieblm^udhe_[ZgbcdZ`^h]hba]jmah\±[m^mlgZ[ex^Zlvky©[b_gbyª.<<<<<<<<3) We_dljbq_kdb_hkpbeeylhju:JZkkfhljbf dhglmj ij_^klZ\e_ggucgZjbkmgd_BaijZ\beDbjo]hnZdI1 q2 q1− C − L dt + C = 01; I1 = q1 , I 2 = q2 ;− q3 − L dI 2 + q2 = 0 Cdt C1q1 + q2 + q3 = 0,<<q1 q1 + q3 L q1 + C + C = 01lh]^Z .qq+ L q + 1 3 + q3 = 0 3C1C<<<<qI L qI + C = 0Keh`bfb\uql_fmjZ\g_gby , ]^_qI = q1 – q3; qII = q1 + q3 – ghj L qII + qII 1 + 2 = 0 C C1 <<<<1 + 2 CC1 1fZevgu_ dhhj^bgZlu ω I =, ω II = ± ghjfZevgu_ qZklhlu A^_kv \gh\vLCLdZdb\gZ[ex^Z_lkyZgZeh]byf_`^mf_oZgbq_kdbfbbwe_dljbq_kdbfbdhe_[Zgbyfb64) H[sbcf_lh^hij_^_e_gbyghjfZevguodhhj^bgZl:<kemqZ_\ha[m`^_gbyh^ghcbaghjfZevguofh^l_eZdhe_[exlky\h^ghcnZa_ beb \ijhlb\hnZa_ ihwlhfm \ h[s_f kemqZ_ ^ey ihbkdZ ghjfZevguo dhhj^bgZl j_r_gby ξ1 b ξ2bsml\\b^_AIcosω1t bBIcosω1t.
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