\documentclass[convert=true,convert={convertexe={convert},density=1200,outext=.png}]{standalone}

\input{figsDefs.tex}

\begin{document}
	
\begin{tikzpicture}%
	% rayon
	\pgfmathsetmacro{\valR}{2};
	% trajectoire
	\draw[thick,blue] (0,0) circle (\valR);
	\draw[blue] (120:\valR) node[above left] {$\Gamma$};
	% m et s
	\pgfmathsetmacro{\valAngle}{30};
	\draw[thick,absCol] (-50:\valR) arc (-50:\valAngle:\valR);
	\draw[absCol] (-5:\valR) node[right] {$s$};
	\draw[blue,fill] (-50:\valR) circle (0.05) node[below right] {$O$};
	\draw (-50:0.9) arc (-50:\valAngle:0.9);
	\draw (-20:0.9) node[right] {$\varphi$};
	\draw[dashed] (0,0) -- (-50:\valR);
	
	\pgfmathsetmacro{\valAngleCompl}{90+\valAngle};
	\path (\valAngle:\valR) node[coordinate] (P) {};
	\path ($-1*(\valAngle:1)$) node[coordinate] (eN) {};
	\path (\valAngleCompl:1) node[coordinate] (eT) {};
	\draw[decorate,decoration={brace,raise=8pt}] (0,0) -- node[above=4mm,sloped] {$R$} (P);
	\draw[thick,fill] (P) circle (0.05) node[right] {$m$};%
	\draw[dashed] (P)+(-0.4,-.4) rectangle ++(.6,.4);
	% M
	\draw[thick,fill] (0,0) circle (0.05) node[below left] {$C$};%
	% vecteurs
	\draw[->,>=latex,thick,forceCol] (P) -- +($1.5*(eN)$) node[below,pos=0.9] {$\vec{F}_n$};%
	\draw[->,>=latex] (P)++(0.05,-.05) -- +(eN) node[below,pos=0.7] {$\vec{e}_n$};%
	\draw[->,>=latex,thick,forceCol] (P) -- +($1.3*(eT)$) node[above,pos=1] {$\vec{F}_t$};%
	\draw[->,>=latex] (P)++(0.05,.05) -- +(eT) node[right=2pt,pos=0.8]{$\vec{e}_t$};%
	
	% sens positif
	\draw[thick,->,>=latex] (-20:3.5) arc (-20:20:3.5);
	\draw[] (4.6,0.5) node {sens positif};
	\draw[] (4.4,0) node {(choix)};
	
\end{tikzpicture}%

\end{document}