Problem in typing a symbol

Question

I want to type this character as a symbol for energy:

But when I type capital u, it is shown as:

Please help me find the solution. Thanks

Answer 1

If you want U from the default Computer Modern font you can just define it using another name. I used \energy because that is what you want to use it for.

\documentclass{article}

% Change the main math font
\usepackage{mathpazo}

% Get Computer Modern ``U'' back under different name
\DeclareSymbolFont{cmletters}{OML}{cmm}{m}{it}
\DeclareMathSymbol{\energy}{\mathalpha}{cmletters}{`U}

\begin{document}

$U \energy$

\end{document}