$T-mg = {{mv^2} \over r}$ at lowest point
+ $E_K_{\text{bottom}}=E_K_{\text{top}}+mgh$
+
% -----------------------
\subsection*{Projectile motion}
\begin{itemize}
\[W={1\over2}mv^2=qV \tag{field or points}\]
\[v=\sqrt{{2qV} \over {m}}\tag{velocity of particle}\]
+ Circular path: $F\perp B \perp v$
+
% -----------------------
\subsection*{Power transmission}
% -----------------------
\subsection*{Polarisation}
\includegraphics[height=3.5cm]{graphics/polarisation.png} \\
- Reduces total amplitude
+ Reduces total amplitude (transverse only)
% -----------------------
\subsection*{Diffraction}
\subsection*{Refraction}
\includegraphics[height=3.5cm]{graphics/refraction.png}
- When a medium changes character, energy is \emph{reflected}, \emph{absorbed}, and \emph{transmitted}
+ When a medium changes character, light is \emph{reflected}, \emph{absorbed}, and \emph{transmitted}
angle of incidence $\theta_i =$ angle of reflection $\theta_r$
$n_1 v_1 = n_2 v_2$
+ $n={c \over v}$
+
% +++++++++++++++++++++++
\section{Light and Matter}