added hydrogen spectrum

1 files changed, 8 insertions, 2 deletions

diff --git a/spectr.tex b/spectr.tex
index 3ebb8d3..6a32ad0 100644
--- a/spectr.tex
+++ b/spectr.tex
@@ -300,8 +300,12 @@ where $m$ is the diffraction order, and $d$ is the distance between the lines in
     Also, turn on the sodium lamp as soon as you arrive, since it requires 10-15 minutes to warm up
     and show clear Na spectrum.
 
-\subsection*{Experimental studies of Hydrogen Balmer line}
+\subsection*{Experimental studies of Hydrogen Balmer series}
 
+\begin{figure}[h]
+	\includegraphics[width=\linewidth]{./pdf_figs/Emission_spectrum-H}
+	\caption{\label{fig:hydrogen_visible_spectrum} Hydrogen visible spectrum}
+\end{figure}
 Swing the rotating telescope slowly and determine which spectral lines from Balmer series you
 observe. You should be able to see three bright lines - Blue, Green and Red - in the first (m=1) and
 second (m=2) diffraction orders on both left \& right sides. In the third order (m=3) only the Blue,
@@ -309,7 +313,9 @@ second (m=2) diffraction orders on both left \& right sides. In the third order
 
 One more line of the Balmer series is in the visible range - Violet, but its intensity is much lower
 than for the other three line. However, you will be able to find it in the first order if you look
-carefully with the collimator slit open a little wider.
+carefully with the collimator slit open a little wider. You should see
+spectrum resembling one shown in Fig.~\ref{fig:hydrogen_visible_spectrum}.
+
 %
 %\emph{Lines to be measured:}
 %\begin{itemize}