105 lines
4.9 KiB
TeX
105 lines
4.9 KiB
TeX
\documentclass[10pt,letterpaper,twoside,openright]{article}
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\usepackage[utf8]{inputenc}
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\usepackage{amsmath}
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\usepackage{amsfonts}
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\usepackage{amssymb}
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\usepackage{graphicx}
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\usepackage{siunitx}
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\usepackage{lmodern}
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\usepackage{fourier}
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\usepackage{tabularray}
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\usepackage{enumitem}
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\usepackage{floatflt} % Floating images with good spacing
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\usepackage{tcolorbox} % Colored boxes
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\usepackage{framed} % To put frames around our images
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\usepackage[
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% showframe,
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inner=20mm,
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outer=20mm,
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top=20mm,
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bottom=20mm,
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bindingoffset=10mm,
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marginparsep=10mm,
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marginparwidth=25mm,
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includemp, % to include marginparsep and marginparwidth
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]{geometry}
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%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
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%% Miscellaneous Commands %%%%%%%%%%%%%%%%%%%%%
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\graphicspath{{images/}}
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\renewcommand{\baselinestretch}{1.2}
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\setlength{\FrameSep}{3mm}
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\setlength{\OuterFrameSep}{0mm}
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%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
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%% Style our margin notes %%%%%%%%%%%%%%%%%%%%%
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%% https://tex.stackexchange.com/a/58266/245702
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\NewCommandCopy{\oldmarginpar}{\marginpar}
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\RenewDocumentCommand{\marginpar}{om}{%
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\IfNoValueTF{#1}
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{\oldmarginpar{\mymparsetup #2}}
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{\oldmarginpar[\mymparsetup #1]{\mymparsetup #2}}}
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\newcommand{\mymparsetup}{\raggedright\sffamily\footnotesize}
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\author{Kenneth John Odle}
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\title{Significant Figures}
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\usepackage{lipsum}
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\begin{document}
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\maketitle
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Like many people, scientists often spend their days measuring things. They use a wide variety of measuring tools, from rulers to digital balances. Any measurement tool is limited in its accuracy. A conventional bathroom scale can give us a weight in pounds, but it does not have the accuracy required to weigh an apple accurately. Likewise, a kitchen balance can give us the weight of an apple in tenths of an ounce, but could not accurately weigh \SI{100}{\milli\gram} of sugar.
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No measuring device is 100\% accurate, and so there is always a small amount of uncertaintly in our measurements. Thus, every\marginpar[Measurements]{Measurements} measurement contains a number of digits that we know for certain to be accurate, and a final digit that is an estimate. These digits—the digits we are certain about, plus the one that is an estimate only—are called \textit{significant figures}.
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\begin{floatingfigure}{0.45\textwidth}
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\begin{framed}
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\centering
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\includegraphics[width=0.8\textwidth]{balance_01}
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\caption{A balance displaying mass in grams.}
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\label{fig:balance1}
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\end{framed}
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\end{floatingfigure}
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For example, the balance displayed in Figure \ref{fig:balance1} is showing a weight of \SI{3.23}{\gram}. The first two digits are accurate, and the third digit (3) is the balance's estimate of that value. In other words, the value here could be \SI{3.22}{\gram}, \SI{3.23}{\gram}, or \SI{3.24}{\gram},
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In this case, we would say that this balance can accurately estimate the mass to the nearest one-hundredth of a gram. We are certain that the \SI{3.2} portion is correct, and we accept that the third digit has an acceptable level of uncertainty in it.
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Uncertainty\marginpar[Symbol for uncertainty]{Symbol for uncertainty} in measurements is denoted by $\sigma_x$ (``sigma sub x''). In digital instruments, the uncertainty is simply the smallest increment the device shows. In the case of our balance above, $\sigma_x$ = \SI{0.01}{\gram}.
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For analog instruments that have a scale on them, such as a ruler or thermometer, the uncertainty is the smallest increment the device shows divided by two.
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\begin{tcolorbox}
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\lipsum[7]
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\end{tcolorbox}
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\lipsum[2-5]
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\begin{tcolorbox}[sharp corners, colback=red9, colframe=red4, title=Another paragraph with title]
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\lipsum[2]
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\end{tcolorbox}
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\section{Rules for Determining Significant Figures}
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The following guidelines indicate whether or not a digit is significant.
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\begin{enumerate}[nolistsep]
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\item Any non-zero number is significant.
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\item Any zero between two non-zero numbers is significant.
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\item Leading zeros (i.e, zeros at the beginning of a number, either before or after the decimal point) are not significant.
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\item Trailing zeros (i.e., zeros at the end of a number) are significant only if a decimal point is present.
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\end{enumerate}
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The\marginpar[Scientific Notation]{Scientific Notation} last two rules are often confusing. Rewriting numbers with a significant number of leading or trailing in scientific notation can help to reduce ambiguity because leading zeros get converted to an exponent and trailing zeros depend on the presence of a decimal point.
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\section{Rules for Using Significant Figures in Calculations}
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\begin{tcolorbox}[sharp corners, colback=yellow9, colframe=yellow7, title=\textbf{\sffamily Caution:}]
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The rules for using significant figures in calculations are fairly straightforward. Where most people make a mistake is in using the wrong set of rules for their calculations, such as using the rules for addition and subtraction when they are actually multiplying or dividing.
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\end{tcolorbox}
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\subsection{Addition and Subtraction}
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\subsection{Multiplication and Division}
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\end{document} |