\documentclass[tikz]{standalone}\input{pre.tex}\begin{document}\begin{tikzpicture}[
force/.style={>=latex,draw=blue,fill=blue},
% axis/.style={densely dashed,gray,font=\small},
axis/.style={densely dashed,black!60,font=\small},
interface/.style={
pattern = north east lines,
draw = none,
pattern color=gray!60,
},
cargo/.style={
rectangle,
fill=magenta!40,
draw=black!50,
inner sep=2.5mm,
},
spring/.style={
decoration={
aspect=0.3,
segment length=.8mm,
amplitude=2mm,
coil},
decorate,
draw=magenta!25
},
interface1/.style={draw=gray!60,
% The border decoration is a path replacing decorator.
% For the interface style we want to draw the original path.
% The postaction option is therefore used to ensure that the
% border decoration is drawn *after* the original path.
postaction={draw=gray!60,decorate,decoration={border,angle=-135,
amplitude=0.3cm,segment length=2mm}}},
]
\def\angle{41}
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
\draw[thick, interface] (0,0) rectangle ++(4,-0.25);
\draw[thick] (0,0) -- ++(4,-0);
\draw[magenta!50,line join=round,line width=5pt,dash pattern={on 7pt off 2pt on 7pt off 2pt}] (1,2.85pt) -- ++(3,0) -- ++ (2.5pt,0) -- ++(0,-1.1);
% \draw[black!10] (4,0) -- ++(0,1);
\begin{scope}[yshift=0.5cm]
\draw[axis,->] (-1,1) -- (5,1)
node [right] {$+x$};
\draw[black] (1,0.9) -- ++(0,0.2) node[above] {$0$};
\draw[black] (4,0.9) -- ++(0,0.2) node[above] {$(1-\eta)\cdot l$};
\end{scope}
\draw[axis,->] (6,1) -- ++(0,-2.2)
node [below] {$+y$};
\draw[black] (5.9,0) -- ++(0.2,0) node[right] {$0$};
\draw[black] (5.9,-1) -- ++(0.2,0) node[right] {$\eta l$};
\draw[force,->] (2.5,0) -- ++(-3,0) node[left] {$\vec{f}_R$};
\draw[force,->] (2.5,0) -- ++(0,-0.8) node[below] {$(1-\eta)m\vec{g}$};
\draw[force,->] (2.5,0) -- ++(0,0.8) node[above] {$\vec{N}$};
\draw[force,->] (4.1,-0.5) -- ++(0,1) node[above] {$\vec{T}'$};
\draw[force,->] (4.1,-0.5) -- ++(0,-1) node[below] {$\eta m \vec{g}$};
\draw[force,->] (2.5,0.1) -- (4.6,0.1) node[above] {$\vec{T}$};
% \draw[axis] (4,0) -- ++(1,0);
% \draw[axis] (4,-1) -- ++(1,0) ;
% \draw[axis,<->] (5,0) -- node[right,black] {$\eta l, m_2=\eta m$} (5,-1);
\end{tikzpicture}\end{document}
