Chapter 19 complete

content/chapter02.tex

@@ -42,9 +42,13 @@
 			\begin{axis}[
 				axis lines = left,
 				xlabel = \(t\),
-				ylabel = \(s\)
+				ylabel = \(s\),
+				ymin = 0
 			]
 				\addplot [domain=0:10] {x^3};
+				\addplot [gray, domain=0:10] {168.75*x - 843.75};
+				\filldraw (axis cs:7.5, 421.875) circle (0.25mm);
+				\draw [dashed, gray] (axis cs: 7, 337.5) -- (axis cs: 8,337.5) -- (axis cs: 8,506.25);
 			\end{axis}
 		\end{tikzpicture}
 		\end{center}

content/chapter05.tex

@@ -14,9 +14,9 @@
 				\draw (0,-0.2) rectangle (4,0.2);
 				\draw [dotted] (0,0) -- (0,-2);
 				\filldraw [fill=white, draw=black] (0,0) circle (3mm);
-				\draw [line width=0.5mm, -stealth] (4,-2) -- (4,-0.2) node[pos=0.5, anchor=west] {\(F\)};
-				\draw [stealth-stealth] (0,-1.8) -- (4,-1.8) node[pos=0.5, anchor=north] {\(r\)};
-				\draw (0.3,-1)[line width=0.5mm, -stealth] arc (-90:0:0.5) node[pos=0.5, anchor=north west] {turning motion};
+				\draw [line width=0.5mm, -latex] (4,-2) -- (4,-0.2) node[pos=0.5, anchor=west] {\(F\)};
+				\draw [latex-latex] (0,-1.8) -- (4,-1.8) node[pos=0.5, anchor=north] {\(r\)};
+				\draw (0.3,-1)[line width=0.5mm, -latex] arc (-90:0:0.5) node[pos=0.5, anchor=north west] {turning motion};
 			\end{tikzpicture}
 		\end{center}
 

content/chapter06.tex

@@ -28,7 +28,7 @@
 				\draw [dotted] (-4,3) -- (0,3);
 				\path (0,1) -- (0.5,1) node[anchor=west] {\(P_2\)}; 
 				\draw [dotted] (0,1) -- (-4,1);
-				\draw [stealth-stealth] (-2,3) -- (-2,1) node[pos=0.5, anchor=west]{\(\Delta h \)};
+				\draw [latex-latex] (-2,3) -- (-2,1) node[pos=0.5, anchor=west]{\(\Delta h \)};
 			\end{tikzpicture}
 			\[\Delta P = \left| P_2 - P_1 \right| = \rho g \Delta h\]
 		\end{center}

content/chapter09.tex

@@ -12,7 +12,7 @@
 		\begin{tikzpicture}
 			\draw (0,0) [anchor=north] node {hotter region} rectangle (5,0.5) node [anchor=south] {colder region};
 			\shade [left color=red, right color=blue] (0,0) rectangle (5,0.5);
-			\draw [line width=0.5mm, -stealth] (0,-1) -- (5,-1) node [pos=0.5, anchor=north] {flow of heat};
+			\draw [line width=0.5mm, -latex] (0,-1) -- (5,-1) node [pos=0.5, anchor=north] {flow of heat};
 		\end{tikzpicture}
 	\end{center}
 

content/chapter13.tex

@@ -104,7 +104,7 @@
         n_1 \sin \theta_c &= n_2 \sin \SI{90}{\degree} \\
         \sin \theta_c &= \frac{n_2 (1)}{n_1} \\
         \sin \theta_c &= \frac{n_2}{n_1} \\
-        \theta_c &= \sin^{-1} \left(\frac{n_2}{n_1}\right)
+        \theta_c &= \boxed{\sin^{-1} \left(\frac{n_2}{n_1}\right)}
     \end{align*}
 
 	\pdef{Total Internal Reflection}{Total internal reflection is the complete reflection of a light ray inside an optically denser medium at its boundary with an optically less dense medium.}

content/chapter19.tex

@@ -0,0 +1,78 @@
+\documentclass[../main.tex]{subfiles}
+
+\begin{document}
+	\section{Practical Electricity}
+	\begin{preamb}
+		In this chapter we will explore electricity in everyday life and electrical safety.
+	\end{preamb}
+
+	\subsection{Electrical Energy and Power}
+	\peqn{Electrical Power}{Electrical power can be calculated with the equations}{P = IV = I^2R = \frac{V^2}{R}}
+
+	\peqn{Electrical Energy}{Because \(E = Pt\), we multiply all the above equations by \(t\)}{E = IVt = I^2Rt = \frac{V^2}{R}t}
+
+	\peqn{Cost of Electricity Consumption}{The cost of using some amount of electrical energy can be calculated in the equation}{\text{cost} = E \times \text{rate}}
+	Sometimes the preferred unit of electrical energy consumed is kilowatt hours [\si{\kilo\watt\hour}] to make calculating cost easier.
+
+	\subsection{Hazards of Electricity}
+	Electricity can be powerful but dangerous. The following are notable examples where electricity can cause a hazard. 
+	\begin{itemize}
+		\item \textbf{Damaged Insulation} \begin{itemize}
+			\item Damaged insulation can occur when the insulating material of a cable experiences wear and tear over time, leaving in exposed conducting wires.
+			\item These exposed conducting wires can cause electric shocks if touched.
+		\end{itemize}
+		\item \textbf{Damp Environments} \begin{itemize}
+			\item Water is conductive, \textit{even if it is pure}. \begin{itemize}
+				\item \(\ce{H2O(l) <=>} \underbrace{\ce{H+(aq) + OH-(aq)}}_{\text{mobile charges}}\)
+%				lol i loaded the entire mhchem package just to write this one line
+			\end{itemize}
+			\item Water coming into contact with uninsulated electrical wires provides a conducting path for current.
+		\end{itemize} 
+		\item \textbf{Overheating of Cables} \begin{itemize}
+			\item Overloading of sockets can cause too high of current draw.
+			\item Due to the heating effect of current, if the current exceeds the power rating of a wire or electrical component, it may damage the component or start an electrical fire.
+		\end{itemize}
+	\end{itemize}
+
+	\subsection{Safety Features in Home Circuitries}
+	\subsubsection{Circuit Breakers}
+	\pdef{Circuit Breaker}{A circuit breaker is a safety device that can switch off the electrical supply in a circuit when large currents flow through it.}
+	Circuit breakers can be reset by the user.
+
+	\subsubsection{Fuses}
+	\pdef{Fuse}{A fuse is a safety device added to an electrical circuit to prevent excessive current flow.}
+	Fuses have a certain current rating which we will call \(I_0\). The following shows what happens to the fuse if some current \(I\) is passed through it.
+	\[
+		\text{fuse} \begin{cases}
+			\text{not blown} & I \leqslant I_0 \\
+			\text{blown} & I > I_0
+		\end{cases}
+	\]
+
+	\subsubsection{Switches}
+	\pdef{Switches}{Switches are designed to break or complete an electrical circuit. They should be fitted to the live wire of the appliance.}
+	\begin{center}
+		\begin{circuitikz}
+			\draw (0,0) to [fuse, l=fuse] (1.5,0) to [spst] (3,0) to[european resistor, l=load] (3,-2) -- (0,-2);
+			\draw [o-] (-0.5,0) node[anchor=east] {\SI{240}{\volt}} -- (0,0);
+			\draw [o-] (-0.5,-2) node[anchor=east] {\SI{0}{\volt}} -- (0,-2);
+		\end{circuitikz}
+	\end{center}
+
+	\subsubsection{Earthing}
+	\pdef{Earthing}{Earthing is the method of connecting a wire from the appliance to earth so that unsafe currents can safely flow to earth without hurting the user.}
+
+	\subsubsection{Three-pin Plugs}
+	\pdef{Three-pin Plugs}{Three pin plugs contain three wires: earth, ground, and neutral. They also have a fuse.}
+	The earth wire is \textcolor{green!50!black}{\bf green} and \textcolor{yellow!50!black}{\bf yellow}; the live wire is \textcolor{red!50!black}{\bf brown}; the neutral wire is \textcolor{blue!80!yellow}{\bf blue}.
+
+	Viewing the three pin plug with its casing removed, the live (b\textcolor{red!50!black}{\bf R}own) wire goes to the \textcolor{red!50!black}{\bf R}ight (\(\rightarrow\)); the neutral (b\textcolor{blue!80!yellow}{\bf L}ue) wire goes to the \textcolor{blue!80!yellow}{\bf L}eft (\(\leftarrow\)).
+
+	\subsubsection{Double Insulation}
+	Double insulation is used if the appliance uses a two pin plug. It provides two levels of insulation:
+	\begin{enumerate}
+		\item The electric cables are insulated from the internal components of the appliance.
+		\item The internal components are insulated from the external casing.
+	\end{enumerate}
+	If double insulation is available, but a three-pin plug is present, the earth connector is most likely a dummy one just to allow the appliance to plug in.
+\end{document}

main.tex

@@ -16,6 +16,7 @@
 \usepackage{parskip}
 \usepackage{unicode-math}
 \usepackage{hyperref}
+\usepackage[version=4]{mhchem}
 
 \setmainfont{STIX Two Text}
 \setmathfont{STIX Two Math}
@@ -128,6 +129,7 @@ \part{Electricity and Magnetism}
 \subfile{content/chapter16}
 \subfile{content/chapter17}
 \subfile{content/chapter18}
+\subfile{content/chapter19}
 \end{multicols*}
 
 \end{document}