{VERSION 2 3 "APPLE_68K_MAC" "2.3" } {USTYLETAB {CSTYLE "Maple Input" -1 0 "Courier" 0 1 255 0 0 1 0 1 0 0 1 0 0 0 0 }{CSTYLE "" -1 256 "" 0 1 255 0 0 1 0 1 0 0 0 0 0 0 0 } {CSTYLE "" -1 257 "" 0 1 255 0 0 1 0 1 0 0 0 0 0 0 0 }{PSTYLE "Normal " -1 0 1 {CSTYLE "" -1 -1 "" 0 1 0 0 0 0 0 0 0 0 0 0 0 0 0 }0 0 0 -1 -1 -1 0 0 0 0 0 0 -1 0 }{PSTYLE "" 0 257 1 {CSTYLE "" -1 -1 "" 0 1 0 0 0 0 0 1 0 0 0 0 0 0 0 }3 0 0 -1 -1 -1 0 0 0 0 0 0 -1 0 }} {SECT 0 {EXCHG {PARA 257 "" 0 "" {TEXT -1 26 "Heat Flow and Diffusion, I" }}{PARA 0 "" 0 "" {TEXT -1 0 "" }}{PARA 0 "" 0 "" {TEXT -1 216 "Th e cell below works with a model that is similar to the models we used \+ in the previous module. We include it here to facilitate comparisons \+ between the models in this module and the models in the previous modul e. " }{TEXT 256 16 "Evaluate it now." }}{PARA 0 "" 0 "" {TEXT -1 0 " " }}}{EXCHG {PARA 0 "> " 0 "" {MPLTEXT 1 0 365 "with(plottools):\nwith (plots):\n\nAmbient := t -> sin(3.1416 * t / 12):\n\nEndTime := 72:\n \nk := 0.50:\n\nIVP := \{diff(T(t), t) = k * (Ambient(t) - T(t)),\n \+ T(0) = 3\}:\n\nsolution := dsolve(IVP, \{T(t)\}, numeric):\n\nplt := display(\{odeplot(solution, [t, T(t)], 0..EndTime, color=red)\}): \n\ngraf := plot(Ambient(t), t = 0..EndTime, -3..3, color=blue):\n\ndi splay([plt, graf]);" }}}{EXCHG {PARA 0 "" 0 "" {TEXT -1 0 "" }}{PARA 0 "" 0 "" {TEXT -1 80 "The next cell works with a model like the first model discussed in this module. " }{TEXT 257 115 " Evaluate it now an d then compare it to the model above. Then use this cell as a basis f or further experimentation" }{TEXT -1 1 "." }}{PARA 0 "" 0 "" {TEXT -1 0 "" }}}{EXCHG {PARA 0 "> " 0 "" {MPLTEXT 1 0 642 "k := 0.50:\nc := 0.50:\n\nExterior := t -> sin(3.1416 * t / 12):\n\nIVP := \{diff(Inte rior(t), t) = c * (Brick(t) - Interior(t)),\n diff(Brick(t), t) = k * (Exterior(t) - Brick(t)) +\n k * (In terior(t) - Brick(t)),\n Interior(0) = 3,\n Brick(0) = 2 \}:\n\nsolution := dsolve(IVP, \{Interior(t), Brick(t)\}, numeric):\n \nplot1 := display(\{odeplot(solution, [t, Brick(t)], \n \+ 0..EndTime, color=red)\}):\n\nplot2 := display(\{odeplot(solution, [t, Interior(t)], \n 0..EndTime, color=blue)\}):\n\n graf := plot(Exterior(t), t = 0..EndTime, -3..3, color=black):\n\ndisp lay([plot1, plot2, graf]);" }}}{EXCHG {PARA 0 "> " 0 "" {MPLTEXT 1 0 0 "" }}}}{MARK "0 2 1" 16 }{VIEWOPTS 1 1 0 1 1 1803 }