拉伸载荷沿其长度拉伸或拉动物体或结构的载荷

Question

\begin{tikzpicture}
\draw[thick] (0,0) -- (4,0); % rod
\draw[->,>=stealth] (0,0) -- (-1,0) node[left] {$P$}; % left force
\draw[->,>=stealth] (4,0) -- (5,0) node[right] {$P$}; % right force
\node[below] at (2,0) {Tensile load};
\end{tikzpicture}