Drawing schematics or figures

Question

I would like to have a way to draw like what you can find in the Feynman Lectures on Physics. For instance here here more precisely something like Fig.14-6 or Fig.14-7.

So far using circuitikz and tikz I have:

\documentclass{article}
\usepackage[european]{circuitikz}
\usepackage{tikz}
\usetikzlibrary{patterns}

\begin{document}
\begin{circuitikz}
\draw
(0,0) to [battery1] (2,0) --
(2,2) to [R, i<_=i] (0,2) --
(0,0);
\begin{tikzpicture}
\draw[pattern=north west lines, pattern color=black] (0.65,4.20) rectangle (1.65,3.80);
\end{tikzpicture}
\end{circuitikz}
\end{document}

I'm using a rectangle instead of a resistor so I can have the crosshatch section but doesn't come out right.

Answer 1

You can start testing things through Visual tikz documentation, you also have the option to import images using the graphicxpackage, preferably in pdf format, for that matter all the images that you provide on that page are in svg format, you can edit them at your whim opening them in inkscape, or exporting them in pdf format for use with tikz; Here is an example of how to draw using multiple types of macros, and import an image, as you will not lose the vector format, or transparency.

RESULT-1: Running only tikz macros for drawing manually like.

RESULT-2: If you uncomment lines 25 and 42, of the MWE code, the background is added, and if you download the image and convert to a pdf format in the same folder and save it as imag1.pdf, the graphicx macro insert the pdf file without loosing svg properties. In the result the image above is the imported pdf file and below the tikz code generated.

RESULT-3: Uncomment all instruction lines, is imported the second image, saved as imag2.pdf, and the same pdf output from the actual code is inserted, it causes a warning message: multiples pdfs with page group included in a single page, it crashes for three iterations but you can get.

RESUME: You do not necessarily have to draw everything in tikz, you can import images and those that are in svg, that converting them into pdf can be included without problems. in the conversion if you use inkscape you can edit the image in svg, if you are lucky, you can ungroup each part of the drawing and remove the texts, then you can include them by tikz, or else you can give yourself the work of modify some in inkscape like the image below, I think that if the image requires many macros of manual positioning in tikz it is not very practical, instead you can use other programs type WYSIWYG, then import them and add the texts if you think that in those programs the tipeseting is not good.

MWE:

\documentclass{standalone}
\usepackage[scaled]{helvet}% For serif family font that allows bold and italy
\usepackage{graphicx}
\usepackage[european]{circuitikz}
\usepackage{tikz}
\usetikzlibrary{patterns,backgrounds,arrows.meta,positioning}
% Font configurtation
\renewcommand*\familydefault{\sfdefault} % Set font to serif family
\DeclareTextFontCommand{\textbfit}{%
  \fontseries\bfdefault % change series without selecting the font yet
  \itshape
}

%Create a new patern for firefox and adobe reader from https://tex.stackexchange.com/a/219808/154390
\pgfdeclarepatternformonly{north east lines b}{\pgfqpoint{0pt}{0pt}}{\pgfqpoint{3.4pt}{3.4pt}}{\pgfqpoint{3.4pt}{3.4pt}}%
{
  \pgfsetlinewidth{0.5pt}
  %Principal line
  \pgfpathmoveto{\pgfqpoint{0pt}{0pt}}
  \pgfpathlineto{\pgfqpoint{3.4pt}{3.4pt}}
  %Complement line north east
  \pgfpathmoveto{\pgfqpoint{-1pt}{2.4pt}}
  \pgfpathlineto{\pgfqpoint{1pt}{4.4pt}}
  %Complement line south west
  \pgfpathmoveto{\pgfqpoint{2.4pt}{-1pt}}
  \pgfpathlineto{\pgfqpoint{4.4pt}{1pt}}
  \pgfusepath{stroke}
}

\begin{document}
\begin{tikzpicture}[
    background rectangle/.style={% Background style
            rectangle, 
            rounded corners,
            shade,
            opacity=0.8,
            top color=black!3,
            bottom color=blue!30,
            draw=black!40!blue!60,
            },
       %show background rectangle, %Uncoment to get the background for crazy result
    %Environment Config
    font=\sf,
    %Style Config
    Dashed/.style ={
        pattern=north east lines b,
        pattern color=black,
        draw,
        thick,
        },
    Arrow/.style ={
        -{Kite[inset=0pt,scale =1.5]},
        thick
        }
]
%Downloaded image from http://www.feynmanlectures.caltech.edu/img/FLP_III/f14-06/f14-06_tc_big.svgz
%Svg file opened in inkscape and exported as PDF as imag1.pdf
%Then imported to my tikz drawing using graphicx package
%\node (IMG1) at (0,5){\includegraphics[scale=1]{imag1.pdf}}; % Uncoment to see only the tikz drawing.
%Drawing manually
\draw[Dashed] (-3,-1.7) rectangle ++(0.35,2.6) coordinate (a);
\draw[thick] (a) rectangle ++(6,-2.6) coordinate (b);
\draw[Dashed] (b) rectangle ++(0.35,2.6);
\draw[thick] (-3.75,1.7) node[label={[label distance=-3pt,font=\Large]90:+}]{} |- (-3,-0.4) coordinate (+);
\draw[fill] (+)++(0,3pt) arc (90:270:3pt);
\draw[thick] (4.5,1.7) node[label={[label distance=-3pt,font=\Large]90:--}]{} |- (3.7,-0.4) coordinate (-);
\draw[fill] (-)++(0,-3pt) arc (-90:90:3pt);
\draw[Arrow](-4.3,1.4) -- ++(0,-1.4);
\draw[Arrow](-0.35,-0.35) -- ++(1.4,0);
\node(B) at (0,0.4){\Large\it B};
\node[circle,draw,thick,on grid, right=20pt of B,inner sep=-1.5pt]{\Large$\times$};
\node(J) at (0,-0.9){\Large\it j};
\node(I) at (-4.6,0.8){\Large\it I};
\node at (0.2,1.2){\large $+(-)$};
\node at (0.2,-2){\large $-(+)$};

%Uncomment to get crazy result
%Downloaded image from http://www.feynmanlectures.caltech.edu/img/FLP_III/f14-07/f14-07_tc_big.svgz
%Svg file opened in inkscape and exported as PDF as imag2.pdf in the same folder
%Then imported to my tikz drawing using graphicx package
%\node (IMG1) at (11,5){\includegraphics[scale=1]{imag2.pdf}};
%\node (IMG1) at (11,-3){\includegraphics[scale=0.5]{examplehelp26.pdf}}; % It could make crazy results
\end{tikzpicture}
\end{document}

My Related posts for this issues: Scaling different components of tikzpicture together., 555 timer schematic, How to use Tikz \shade command in order to achieve 3D like results

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UPDATE FOR PATTERNS: SOLUTION FROM tikz pattern north west lines dashed

Answer 2

It is probably my fault to have directed you to circuitikz. I ended up drawing most with basic TikZ syntax.

\documentclass{article}
\usepackage[european]{circuitikz}
\usepackage{tikz}
\usetikzlibrary{patterns,arrows.meta}

\begin{document}
\begin{circuitikz}
\draw
(0,2)  to [battery1] (0,0) -- (4,0) -- (4,2)
--    node[pos=0.8,circle,fill,scale=0.6](left){}
coordinate[pos=0.7] (l) coordinate[pos=0.5] (m) coordinate[pos=0.3] (r)
node[pos=0.2,circle,fill,scale=0.6](right){}
 (0,2) ;
\draw[fill=gray!30] (4.5,1) rectangle (7.5,6);
\draw[fill=white] (6,4) circle (1cm);
\draw[-latex,thick] (6,3.2) -- (6.4,4.4);
\draw (6,4.8) -- (6,5) node[above,font=\sffamily]{0};
\node[anchor=south west,fill=white] at (4.5,5){$-$};
\node[anchor=south east,fill=white] at (7.5,5){$+$};
\draw[-Circle] (m) -- ++(0,0.5) -- ++(3,0);
\draw[-Circle] (m) -- ++(0,-0.5) -- ++(3,0) -- ++(0,0.5);
\draw[fill=white] ([yshift=3mm]left) rectangle ([yshift=-3mm]right);
\draw[pattern=north west lines, pattern color=black] 
([yshift=3mm]l) rectangle ([yshift=-3mm]r);
\end{circuitikz}
\end{document}