\documentclass[a4]{article}

\usepackage[utf8]{inputenc}
\usepackage[T1]{fontenc}
\usepackage{lmodern}
\usepackage{amsmath,amsfonts,amssymb}
\usepackage{graphicx}
\usepackage[usenames,dvipsnames]{xcolor}
%\usepackage{tikz}

\usepackage{pgfplots}
\usepackage{tikz,animate}
\usepackage{pgfplots}
\usetikzlibrary{shapes.arrows}
\usetikzlibrary{arrows.meta}

\usetikzlibrary{calc,patterns,angles,quotes}
\begin{document}
\pagestyle{empty}

\hspace{-3cm}
\begin{tikzpicture}
 

\draw[thick] (-7.0,+3.0) rectangle (10.0,7.0);
\draw[thick] (-7.0,-1.0) rectangle (10.0,3.0);
\draw[thick] (-7.0,-5.0) rectangle (10.0,-1.0);

\draw (-6.5,6.3) node [text=black]{{\Huge  $a)$}};
\draw (-6.5,2.3) node [text=black]{{\Huge  $b)$}};
\draw (-6.5,-1.7) node [text=black]{{\Huge  $c)$}};

\draw[-,thick] (-6.0,5.0) -- (9.0,5.0);
\draw[-,thick] (-6.0,1.0) -- (9.0,1.0);
\draw[-,thick] (-6.0,-3.0) -- (9.0,-3.0);


%%%%%%%%%%%%%%%%%%%%%%%%%%%%
% Panel c)

\draw[thick,fill=Cyan,opacity=0.50] (-0.9,-3.4) rectangle (1.1,-2.6);
\draw[thick,fill=blue,opacity=1.00] (-0.2,-3.4) rectangle (0.4,-2.6);

\draw[thick,fill=Cyan,opacity=0.50] (0.7,-3.4) rectangle (2.7,-2.6);
\draw[thick,fill=blue,opacity=1.00] (1.4,-3.4) rectangle (2.0,-2.6);

\draw[thick,black!35,opacity=0.50]  (0.7,-3.4) rectangle (2.7,-2.6);


\draw[thick,fill=Cyan,opacity=0.50] (2.6,-3.4) rectangle (4.6,-2.6);
\draw[thick,fill=blue,opacity=1.00] (3.3,-3.4) rectangle (3.9,-2.6);

\draw[thick,black!35,opacity=0.50]  (2.6,-3.4) rectangle (4.6,-2.6);


%%%%%%%%%%%%%%%%%%%%%%%

\draw[thick,fill=Cyan,opacity=0.50] (-5.6,-3.4) rectangle (-3.6,-2.6);
\draw[thick,fill=Cyan,opacity=0.50] (-4.9,-3.4) rectangle (-2.9,-2.6);
\draw[thick,fill=Cyan,opacity=0.50] (-4.2,-3.4) rectangle (-2.2,-2.6);



\draw[thick,fill=blue,opacity=1.00] (-4.9,-3.4) rectangle (-4.3,-2.6);
\draw[thick,fill=blue,opacity=1.00] (-4.2,-3.4) rectangle (-3.6,-2.6);
\draw[thick,fill=blue,opacity=1.00] (-3.5,-3.4) rectangle (-2.9,-2.6);

\draw[thick,black!35,opacity=0.50] (-4.9,-3.4) rectangle (-4.3,-2.6);
\draw[thick,black!35,opacity=0.50] (-4.2,-3.4) rectangle (-2.2,-2.6);



%\draw[thick,black!35,opacity=0.50]  (3.3,-2.2) rectangle (5.3,-1.8);

%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%

\draw[thick,fill=Cyan,opacity=0.50] (5.6,-3.4) rectangle (7.6,-2.6);
\draw[thick,fill=blue,opacity=1.00] (6.3,-3.4) rectangle (6.9,-2.6);

%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%

% Panel b) 

\draw[thick,fill=Cyan,opacity=0.50] (-5.7,0.6) rectangle (-3.7,1.4);
\draw[thick,fill=blue,opacity=1.00] (-5.0,0.6) rectangle (-4.4,1.4);

\draw[thick,fill=Cyan,opacity=0.50] (-2.6,0.6) rectangle (-0.6,1.4);
\draw[thick,fill=blue,opacity=1.00] (-1.9,0.6) rectangle (-1.3,1.4);

\draw[thick,fill=Cyan,opacity=0.50] (-0.2,0.6) rectangle (1.8,1.4);
\draw[thick,fill=blue,opacity=1.00] (0.5,0.6) rectangle (1.1,1.4);

\draw[thick,fill=Cyan,opacity=0.50] (1.3,0.6) rectangle (3.3,1.4);
\draw[thick,fill=blue,opacity=1.00] (2.0,0.6) rectangle (2.6,1.4);

\draw[thick,black!50,opacity=0.50] (1.3,0.6) rectangle (3.3,1.4);

\draw[thick,fill=Cyan,opacity=0.50] (3.6,0.6) rectangle (5.6,1.4);
\draw[thick,fill=blue,opacity=1.00] (4.3,0.6) rectangle (4.9,1.4);

\draw[thick,fill=Cyan,opacity=0.50] (6.1,0.6) rectangle (8.1,1.4);
\draw[thick,fill=blue,opacity=1.00] (6.8,0.6) rectangle (7.4,1.4);


%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
% Panel a) 

\draw[thick,fill=Cyan,opacity=0.50] (-5.4,4.6) rectangle (-3.4,5.4);
\draw[thick,fill=blue,opacity=1.00] (-4.7,4.6) rectangle (-4.1,5.4);

%\draw[<->,thick] (-5.4,1.5) -- (-3.4,1.5);
%\draw[<->,thick] (-4.7,2.5) -- (-4.1,2.5);
\draw[ultra thick, {Stealth[length=2mm, width=2mm]}-{Stealth[length=2mm, width=2mm]} ] (-5.4,4.3) -- (-3.4,4.3);
\draw[ultra thick, {Stealth[length=1.5mm, width=1.5mm]}-{Stealth[length=1.5mm, width=1.5mm]} ] (-4.7,5.7) -- (-4.1,5.7);

\draw (-3.5, 5.7 ) node [text=black]{{\LARGE  $\sigma_W$}};
\draw (-3.0, 4.3 ) node [text=black]{{\LARGE  $\sigma$}};


\draw[thick,fill=Cyan,opacity=0.50] (-2.4,4.6) rectangle (-0.4,5.4);
\draw[thick,fill=blue,opacity=1.00] (-1.7,4.6) rectangle (-1.1,5.4);

\draw[thick,fill=Cyan,opacity=0.50] (0.1,4.6) rectangle (2.1,5.4);
\draw[thick,fill=blue,opacity=1.00] (0.8,4.6) rectangle (1.4,5.4);


\draw[thick,fill=Cyan,opacity=0.50] (3.1,4.6) rectangle (5.1,5.4);
\draw[thick,fill=blue,opacity=1.00] (3.8,4.6) rectangle (4.4,5.4);

\draw[thick,fill=Cyan,opacity=0.50] (6.6,4.6) rectangle (8.6,5.4);
\draw[thick,fill=blue,opacity=1.00] (7.3,4.6) rectangle (7.9,5.4);
 
\end{tikzpicture}


\end{document}



\begin{tikzpicture}
% z- axis
\draw[->, thin] (0,-5) -- (0,2);
% upper circle

\draw[->,thick, red] (0,0) -- (-0.866025,0.5);
\draw (-0.75,0.2) node [text=red]{ $R_1$};
\draw[-,thin] (-2.5,0) -- (1.8,0);
\draw[thick] (0,-3) circle (1.5);
\draw[thick, blue] (0,-1.29167) circle (0.817559);
\draw[thin, blue] (-2,-1.29167) -- (1.8,-1.29167);
\draw[-,thin] (-2.5,-3) -- (1.8,-3);
\draw[->,thin] (-2.3,-1.4) -- (-2.3,0);
\draw[->, thin] (-2.3,-1.9) -- (-2.3,-3);
\draw (-2.3,-1.65) node [text]{$a$};
\draw[->, thin,blue] (-2.0,-0.4) -- (-2.0, 0.0);
\draw[->, thin,blue] (-2.0,-0.8) -- (-2.0, -1.29167);
\draw (-1.9, -0.6) node [text=blue]{$a_1$};
\draw[->, thin, blue] (-2.0, - 2.0) -- (-2.0,-1.29167) ;
\draw[->, thin, blue] (-2.0, -2.4) -- (-2.0, -3.0);
\draw (-1.9,-2.2) node [text=blue]{$a_2$};
\draw (2.0, -1.0) node [text=blue]{$M$};
\draw (0.2, 1.2) node [text]{$A$};
\draw (0.2, 0.2) node [text]{$B$};
\draw (0.2, -0.3) node [text]{$C$};
\draw (0.2, -0.8) node [text]{\small $D$};
\draw (0.2, -1.15) node [text]{\small $E$};
\draw (0.2, -1.4) node [text]{\tiny $F$};
\end{tikzpicture}


\begin{tikzpicture}
\draw[->, ultra thick] (-1,0) -- (2.5,0);
\draw (2.5,-0.5) node {\Large $x$};
\draw[->, ultra thick] (0,-2.5) -- (0,1);
\draw (-0.5,1) node {\Large $z$};
\draw[-,ultra thick, blue] (0,0) -- (1,-2);
\draw[thick, blue,fill=blue] (1,-2) circle  (0.2);
\draw (1.6,-2.2) node [text=blue]{\Large $m$};
\draw[->,,thick] (0,-1.5) arc[radius=1.2, start angle=270, end angle=300];
%\draw[-,,thick] (-2.,-1.25) arc[radius=2.25, start angle=210, end angle=330];
\draw[thick] (0,0) circle (2.25);
\draw [->, ultra thick, red] (1.5,-0.5) -- (1.5,-1.5);
\draw (0.8,-1.0) node [text=blue]{\Large $l$};
\draw (1.8,-1.0) node [text=red]{\Large $g$};
%pic [draw, ->,''$\varphi$'', angle eccentricity=5.5] {angle =(0,-2) -- (0,0) -- (1,-2)};
\end{tikzpicture}