\documentclass{standalone}
\usepackage[american]{circuitikz}
\usepackage{graphicx}
\usepackage{mathrsfs} 
\usepackage{latexsym,amssymb,amsmath}
\usetikzlibrary{bending}
\newcommand{\equal}{=}
\begin{document}
	\begin{circuitikz}
		\draw (0,3) to [V,l_=$\mathscr{F}\equal NI$] (0,0) 
		(0,3) -- (3,3) 
	    (3,0) -- (0,0) 
	     (3,3) to [R, l^= $\mathscr{R}_{eq}$,v_>=$\mathscr{F}$, color=blue] (3,0);
	     
%	     \draw[thin, <-, >=triangle 45] (1.5,1.5) node[scale=2]{$\phi$}   ++(-90:0.5) arc (-90:100:0.5);
		\node (phi) at (1.5,0.5) {$\phi$};
		\draw[-stealth]  (1.5,2.5) to [bend left=90] (phi);     
		\end{circuitikz}
	\label{fig:q1fig}
\end{document}