#LyX 2.3 created this file. For more info see http://www.lyx.org/ \lyxformat 544 \begin_document \begin_header \save_transient_properties true \origin unavailable \textclass article \begin_preamble \usepackage{siunitx} \usepackage{pgfplots} \usepackage{listings} \usepackage{multicol} \sisetup{output-decimal-marker = {,}, quotient-mode=fraction, output-exponent-marker=\ensuremath{\mathrm{3}}} \end_preamble \use_default_options true \maintain_unincluded_children false \language slovene \language_package default \inputencoding auto \fontencoding global \font_roman "default" "default" \font_sans "default" "default" \font_typewriter "default" "default" \font_math "auto" "auto" \font_default_family default \use_non_tex_fonts false \font_sc false \font_osf false \font_sf_scale 100 100 \font_tt_scale 100 100 \use_microtype false \use_dash_ligatures true \graphics default \default_output_format default \output_sync 0 \bibtex_command default \index_command default \paperfontsize default \spacing single \use_hyperref false \papersize default \use_geometry true \use_package amsmath 1 \use_package amssymb 1 \use_package cancel 1 \use_package esint 1 \use_package mathdots 1 \use_package mathtools 1 \use_package mhchem 1 \use_package stackrel 1 \use_package stmaryrd 1 \use_package undertilde 1 \cite_engine basic \cite_engine_type default \biblio_style plain \use_bibtopic false \use_indices false \paperorientation portrait \suppress_date false \justification false \use_refstyle 1 \use_minted 0 \index Index \shortcut idx \color #008000 \end_index \leftmargin 1cm \topmargin 2cm \rightmargin 1cm \bottommargin 2cm \headheight 1cm \headsep 1cm \footskip 1cm \secnumdepth 3 \tocdepth 3 \paragraph_separation indent \paragraph_indentation default \is_math_indent 0 \math_numbering_side default \quotes_style german \dynamic_quotes 0 \papercolumns 1 \papersides 1 \paperpagestyle default \tracking_changes false \output_changes false \html_math_output 0 \html_css_as_file 0 \html_be_strict false \end_header \begin_body \begin_layout Title Dušeno nihanje nitnega nihala \end_layout \begin_layout Author \noun on Anton Luka Šijanec \end_layout \begin_layout Date 16. november 2022 \end_layout \begin_layout Abstract Poročilo četrte vaje pri predmetu \noun on F41 \noun default na Gimnaziji Bežigrad v 4. letniku. Vaja je potekala 13. oktobra 2022. \end_layout \begin_layout Standard \begin_inset CommandInset toc LatexCommand tableofcontents \end_inset \end_layout \begin_layout Section Zveza med amplitudo hitrosti in amplitudo odmika \end_layout \begin_layout Subsection Naloga \end_layout \begin_layout Standard Razišči zvezo med amplitudo hitrosti in amplitudo odmika pri nihanju nitnega nihala. \end_layout \begin_layout Subsection Potek dela \end_layout \begin_layout Enumerate Ko je nihalo v ravnovesni legi, nastavi ničlo slednika gibanja. \end_layout \begin_layout Enumerate S pomočjo slednika gibanja zajemi podatke za \begin_inset Formula $\SI{60}{\second}$ \end_inset dušenega nihanja nitnega nihala. \end_layout \begin_layout Enumerate Na vsake štiri nihaje odčitaj amplitudo odmika in amplitudo hitrosti in podatke zapiši v tabelo. Ker nihalo nima največje hitrosti, ko je odmik največji, odčitavaj največjo hitrost vedno četrt nihaja prej kot največji odmik. \end_layout \begin_layout Enumerate Nariši graf amplitude hitrosti \begin_inset Formula $v_{0}$ \end_inset v odvisnosti od amplitude odmika \begin_inset Formula $x_{0}$ \end_inset ! Določi naklon grafa in oceni nenatančnost te vrednosti. \begin_inset Newline newline \end_inset \begin_inset ERT status open \begin_layout Plain Layout \backslash begin{lstlisting} \end_layout \begin_layout Plain Layout fit (x*p) "v_od_x.tsv" using 1:2 via p \end_layout \begin_layout Plain Layout \backslash end{lstlisting} \end_layout \end_inset \begin_inset Formula \[ p=\SI{4,52127}{\per\second}\pm\SI{0,1111}{\per\second} \] \end_inset \end_layout \begin_layout Enumerate Iz grafa \begin_inset Formula $x(t)$ \end_inset določi \begin_inset Formula $t_{0}$ \end_inset in določi nenatančnost te vrednosti. Iz tako določenega \begin_inset Formula $t_{0}$ \end_inset in iz naklona grafa \begin_inset Formula $v_{0}(x_{0})$ \end_inset preveri zvezo \begin_inset Formula $v_{0}=x_{0}2\pi/t_{0}$ \end_inset . \end_layout \begin_layout Standard \begin_inset Formula \[ t_{0_{\text{{odčitan}}}}=\frac{{t}}{n}=\SI{1,2806}{\second} \] \end_inset \end_layout \begin_layout Standard \begin_inset Formula \[ t_{0_{\text{{izračunan}}}}=\frac{{2\pi}}{p}=\SI{1,38969}{\second} \] \end_inset \end_layout \begin_layout Standard Red velikosti je enak, vendar se rešitvi razlikujeta. Najverjetneje so bili med zaznavanjem prehodov čez nič za odčitanje \begin_inset Formula $t_{0}$ \end_inset iz grafa \begin_inset Formula $x(t)$ \end_inset lažni pozitivni odčitki. \end_layout \begin_layout Standard \begin_inset Float figure placement H wide false sideways false status open \begin_layout Plain Layout \align center \begin_inset ERT status open \begin_layout Plain Layout \backslash begin{tikzpicture} \end_layout \begin_layout Plain Layout \backslash begin{axis}[width=0.75 \backslash textwidth, scale only axis, ylabel=$v$, domain=-0.1:0.1, ytick pos=left, samples=2 56, xlabel=$x$, xtick pos=bottom] \end_layout \begin_layout Plain Layout \backslash addplot[red, only marks] table [x=x, y=v] {v_od_x.tsv}; \end_layout \begin_layout Plain Layout \backslash addplot[green] (x, {x*(4.52127+0.1111)}); \end_layout \begin_layout Plain Layout \backslash addplot[green] (x, {x*(4.52127-0.1111)}); \end_layout \begin_layout Plain Layout \backslash addplot[red] (x, {x*(4.52127)}); \end_layout \begin_layout Plain Layout \backslash end{axis} \end_layout \begin_layout Plain Layout \backslash end{tikzpicture} \end_layout \end_inset \end_layout \begin_layout Plain Layout \begin_inset Caption Standard \begin_layout Plain Layout \begin_inset CommandInset label LatexCommand label name "fig:graf" \end_inset Graf amplitude hitrosti nihanja v odvisnosti od amplitude odmika nihala. \end_layout \end_inset \end_layout \end_inset \end_layout \begin_layout Section Zmanjševanje amplitude pri dušenem nihanju \end_layout \begin_layout Subsection Naloga \end_layout \begin_layout Standard Potrdi, da se amplituda \begin_inset Formula $x_{0}$ \end_inset pri dušenem nihanju zmanjšuje eksponentno kot \begin_inset Formula $x_{0}(t)=x_{00}e^{-\beta t}$ \end_inset , kjer je \begin_inset Formula $x_{00}$ \end_inset amplituda nihala ob času \series bold \begin_inset Formula $t=\SI{0}{\second}$ \end_inset \series default , \begin_inset Formula $\beta$ \end_inset pa koeficient dušenja. \end_layout \begin_layout Subsection Potek dela \end_layout \begin_layout Enumerate Nariši graf amplitude hitrosti \begin_inset Formula $x_{0}$ \end_inset v odvisnosti od časa! Skozi točke na grafu \series bold \begin_inset Formula $x_{0}(t)$ \end_inset \series default nariši ustrezno eksponentno krivuljo! \begin_inset Newline newline \end_inset \begin_inset ERT status open \begin_layout Plain Layout \backslash begin{lstlisting} \end_layout \begin_layout Plain Layout n=0.1 \end_layout \begin_layout Plain Layout b=0.01 \end_layout \begin_layout Plain Layout fit n*exp(-b*x) "v_od_x.tsv" using 3:4 via n, b \end_layout \begin_layout Plain Layout fit (x*ln) "v_od_x.tsv" using 3:5 via ln \end_layout \begin_layout Plain Layout \backslash end{lstlisting} \end_layout \end_inset \begin_inset Formula \[ n=x_{00}=\SI{0,0943867}{\meter}\pm\SI{0,001524}{\meter} \] \end_inset \begin_inset Formula \[ b=\SI{0,0441715}{\per\second}\pm\SI{0,001038}{\per\second}=\beta \] \end_inset \begin_inset Formula \[ ln=-\beta=\SI{-0,0467447}{\per\second}\pm\SI{0,001239}{\per\second} \] \end_inset \begin_inset Newline newline \end_inset \begin_inset Formula $b$ \end_inset in \begin_inset Formula $ln$ \end_inset , torej \begin_inset Formula $\beta$ \end_inset , pridobljeni pred linearizacijo in po linearizaciji sta skoraj enaki. Razlika med njima se pojavi samo zaradi namerne nenatančnosti računalnika. \end_layout \begin_layout Enumerate Nariši graf \begin_inset Formula $\ln\left(\frac{x_{0}}{x_{00}}\right)$ \end_inset v odvisnosti od časa in iz grafa določi koeficient dušenja \begin_inset Formula $\beta$ \end_inset . Določitev napak v \begin_inset Formula $\ref{enu:Nari=00003D000161i-graf-}.$ \end_inset delu vaje ni potrebna. \begin_inset CommandInset label LatexCommand label name "enu:Nariši-graf-" \end_inset \end_layout \begin_layout Standard \begin_inset Float figure placement H wide false sideways false status open \begin_layout Plain Layout \align center \begin_inset ERT status open \begin_layout Plain Layout \backslash begin{tikzpicture} \end_layout \begin_layout Plain Layout \backslash begin{axis}[width=0.75 \backslash textwidth, scale only axis, domain=0:60, ytick pos=left, samples=256, xlabel=$t$ , xtick pos=bottom, ylabel=$ \backslash sqrt{x^2}$] \end_layout \begin_layout Plain Layout \backslash addplot[only marks] table [x=t, y=absx] {v_od_x.tsv}; \end_layout \begin_layout Plain Layout \backslash addplot[green] (x, {(0.0943867+0.001524)*exp((-0.0441715+ 0.001038)*x)}); \end_layout \begin_layout Plain Layout \backslash addplot[green] (x, {(0.0943867-0.001524)*exp((-0.0441715- 0.001038)*x)}); \end_layout \begin_layout Plain Layout \backslash addplot[black] (x, {0.0943867*exp(-0.0441715*x)}); \end_layout \begin_layout Plain Layout \backslash end{axis} \end_layout \begin_layout Plain Layout \backslash begin{axis}[width=0.75 \backslash textwidth, scale only axis, domain=0:60, xlabel near ticks, samples=16, xlabel=$t$, ylabel near ticks, ytick pos=right, axis y line*=right, ylabel=$ \backslash ln \backslash frac{x_0}{x_{00}}$] \end_layout \begin_layout Plain Layout \backslash addplot[red, only marks] table [x=t, y=ln] {v_od_x.tsv}; \end_layout \begin_layout Plain Layout \backslash addplot[green] (x, {x*(-0.0467447+0.001239)}); \end_layout \begin_layout Plain Layout \backslash addplot[green] (x, {x*(-0.0467447-0.001239)}); \end_layout \begin_layout Plain Layout \backslash addplot[red] (x, {x*-0.0467447}); \end_layout \begin_layout Plain Layout \backslash end{axis} \end_layout \begin_layout Plain Layout \backslash end{tikzpicture} \end_layout \end_inset \end_layout \begin_layout Plain Layout \begin_inset Caption Standard \begin_layout Plain Layout \begin_inset CommandInset label LatexCommand label name "fig:graf-1" \end_inset Graf amplitude nihanja (največjega odmika od osi) v odvisnosti od časa. \end_layout \end_inset \end_layout \end_inset \end_layout \begin_layout Section Uporabljen program \end_layout \begin_layout Standard Za zaznavanje prehoda ničel in generiranje tabel sem spisal majhen program: \end_layout \begin_layout Standard \begin_inset ERT status open \begin_layout Plain Layout \backslash lstinputlisting[language=Python]{preseki.py} \end_layout \end_inset \end_layout \end_body \end_document