\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] (-3.5,+0.0) rectangle (3.5,5.0);
\draw[thick] (-3.5,-5.0) rectangle (3.5,0.0);
\draw[thick] (-3.5,-10.0) rectangle (3.5,-5);

\draw (-3.0,4.3) node [text=black]{{\Large  $(a)$}};
\draw (-3.0,-0.7) node [text=black]{{\Large  $(b)$}};
\draw (-3.0,-5.7) node [text=black]{{\Large  $(c)$}};


%%%%%%%%%%%%%%%%%%%%%%%
% panel a 

\draw[ ultra thick]   (0,4.5)-- (-1.5,   0.5);   
\draw[ ultra thick]   (0,4.5)-- (1.5,   0.5);   
\draw[thick, red] (0, 4.5) circle (0.15);
\draw[thick, black, fill] (0, 4.5) circle (0.01);
\draw (-1.7, 0.5) node [text=black]{\Large $1$};
\draw (1.7, 0.5) node [text=black]{\Large $2$};



\draw[thick, blue, fill] (-0.75, 2.5) circle (0.1);
\draw[thick, blue, fill] (0.75, 2.5) circle (0.1);
\draw[ultra thick, dashed]  (-0.75, 2.5) -- (0.75, 2.5) ; 
\draw (0, 2.0) node [text=black]{\Large $\tilde{r}$};

\draw[ultra thick, dashed]  (-0.75, 2.5) -- (-0.75, 4.5) ;
 
  \coordinate (porigo1) at (-0.75,2.5); 
 \coordinate (pzaxis1) at (-0.75,4.5); 
  \coordinate (pointofcontact1)  at (0,4.5); 
 
 %\pic [draw, thick,  ->, angle eccentricity=1, angle radius =1.7cm] {angle = pointofcontact1--porigo1--pzaxis1};
% \pic [draw, thick,  ->, angle eccentricity=1, angle radius =1.7cm] {angle = pzaxis1--porigo1--pointofcontact1};
\pic [draw, thick,  <-, angle eccentricity=1, angle radius =1.7cm] {angle = pointofcontact1--porigo1--pzaxis1};
 \draw (-1.1, 3.7) node[text=black]{$\theta^{(1)}$};
 
 %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
 % panel b 
 
\draw[ ultra thick]   (0.75,-0.5)-- (0.75,  -4.5);   
\draw[ ultra thick]   (0.75,-1.5)-- (-2.5,  -4.0);   
\draw[thick, red] (0.75, -1.5) circle (0.15);
\draw[thick, black, fill] (0.75, -1.5) circle (0.01);

\draw (-2.5, -4.5) node [text=black]{\Large $1$};
\draw (1.0, -4.5) node [text=black]{\Large $2$};

\draw[ultra thick, dashed]  (0.75, -2.5) -- (-0.55, -2.5) ; 
 \draw[thick, blue, fill] (0.75, -2.5) circle (0.1);
 \draw[thick, blue, fill] (-0.55, -2.5) circle (0.1);
\draw[ultra thick, dashed]   (-0.55, -2.5) -- (-0.55, -0.5) ; 

\draw (0.1, -3.0) node [text=black]{\Large $\tilde{r}$}; 

  \coordinate (porigo2) at (-0.55,-2.5); 
 \coordinate (pzaxis2) at (-0.55,-0.5); 
  \coordinate (pointofcontact2)  at (0.75,-1.5); 
 \pic [draw, thick,  <-, angle eccentricity=1, angle radius =1.2cm] {angle = pointofcontact2--porigo2--pzaxis2};
 \draw (-0.1, -1.8) node[text=black]{$\theta^{(2)}$};

\draw[thick]  (0.45,- 2.5)|-(0.75,-2.2);

%%%%%%%%%%%%%%%%%%%%%%%%%%
% panel c


\draw[thick, blue, fill] (-1.5, -7.268) circle (0.1);
\draw[ ultra thick]   (-2.5,-9.0)-- (-0.5,  -5.536);   
\draw[ultra thick, dashed]  (-1.5, -7.268) -- (0.81, -7.268) ; 

\draw (-0.3, -7.7) node [text=black]{\Large $\tilde{r}$}; 

\draw[thick, blue, fill] (0.81, -7.268) circle (0.1);
%\draw[ ultra thick]   (0.81,-7.268)-- (-0.923,  -6.268);   

\draw[ultra thick, dashed]  (-1.5, -7.268) -- (-1.5, -5.5) ; 

  \coordinate (porigo3) at (-1.5,-7.268); 
 \coordinate (pzaxis3) at (-1.5,-5.5); 
  \coordinate (pointofcontact3)  at (-0.923, -6.268); 
 \pic [draw, thick,  <-, angle eccentricity=1, angle radius =1.5cm] {angle = pointofcontact3--porigo3--pzaxis3};
 \draw (-1.0, -5.35) node[text=black]{$\theta^{(3)}$};



\draw[ ultra thick]   (-0.923,-6.268)-- (2.54,  -8.268);   


\draw[thick, red] (-0.923, -6.268) circle (0.15);
\draw[thick, black, fill] (-0.923, -6.268) circle (0.01);

%\draw[thick, red] (-0.923, -6.268) -- (-0.923+0.259, -6.268-0.15) ;
\draw[thick, black]  (-0.923+0.259, -6.268-0.15) -- (-0.923+0.259-0.15, -6.268-0.15-0.259)  ;
\draw[thick, black]  (-0.923+0.259-0.15, -6.268-0.15-0.259) -- (-0.923-0.15, -6.268-0.15-0.259+0.15)   ;

\draw (-2.5, -9.5) node [text=black]{\Large $1$};
\draw (2.5, -8.8) node [text=black]{\Large $2$};

 
\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, -1.4) 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}