Example of a problem that can be handled by the Culmann method: an object (the grey ovoid) is subjected to four forces that are not all parallel, one force is entirely known (<span class="mwe-math-element"><span class="mwe-math-mathml-inline mwe-math-mathml-a11y" style="display: none;"><math xmlns="http://www.w3.org/1998/Math/MathML" alttext="{\displaystyle {\vec {\mathrm {F} }}_{1}}"><semantics><mrow class="MJX-TeXAtom-ORD"><mstyle displaystyle="true" scriptlevel="0"><msub><mrow class="MJX-TeXAtom-ORD"><mrow class="MJX-TeXAtom-ORD"><mover><mrow class="MJX-TeXAtom-ORD"><mi mathvariant="normal">F</mi></mrow><mo stretchy="false">→<!-- → --></mo></mover></mrow></mrow><mrow class="MJX-TeXAtom-ORD"><mn>1</mn></mrow></msub></mstyle></mrow><annotation encoding="application/x-tex">{\displaystyle {\vec {\mathrm {F} }}_{1}}</annotation></semantics></math></span><img src="https://wikimedia.org/api/rest_v1/media/math/render/svg/6fd1cce2a48647e4dcf2476e89d5e013b0288353" class="mwe-math-fallback-image-inline" aria-hidden="true" style="vertical-align: -0.671ex; width:2.572ex; height:3.176ex;" alt="{\displaystyle {\vec {\mathrm {F} }}_{1}}"></span>), and the directions of the three others (<span class="mwe-math-element"><span class="mwe-math-mathml-inline mwe-math-mathml-a11y" style="display: none;"><math xmlns="http://www.w3.org/1998/Math/MathML" alttext="{\displaystyle {\vec {\mathrm {F} }}_{2}}"><semantics><mrow class="MJX-TeXAtom-ORD"><mstyle displaystyle="true" scriptlevel="0"><msub><mrow class="MJX-TeXAtom-ORD"><mrow class="MJX-TeXAtom-ORD"><mover><mrow class="MJX-TeXAtom-ORD"><mi mathvariant="normal">F</mi></mrow><mo stretchy="false">→<!-- → --></mo></mover></mrow></mrow><mrow class="MJX-TeXAtom-ORD"><mn>2</mn></mrow></msub></mstyle></mrow><annotation encoding="application/x-tex">{\displaystyle {\vec {\mathrm {F} }}_{2}}</annotation></semantics></math></span><img src="https://wikimedia.org/api/rest_v1/media/math/render/svg/1d47a28961ffa47bcea580f6bf15e53c09054390" class="mwe-math-fallback-image-inline" aria-hidden="true" style="vertical-align: -0.671ex; width:2.572ex; height:3.176ex;" alt="{\displaystyle {\vec {\mathrm {F} }}_{2}}"></span>, <span class="mwe-math-element"><span class="mwe-math-mathml-inline mwe-math-mathml-a11y" style="display: none;"><math xmlns="http://www.w3.org/1998/Math/MathML" alttext="{\displaystyle {\vec {\mathrm {F} }}_{3}}"><semantics><mrow class="MJX-TeXAtom-ORD"><mstyle displaystyle="true" scriptlevel="0"><msub><mrow class="MJX-TeXAtom-ORD"><mrow class="MJX-TeXAtom-ORD"><mover><mrow class="MJX-TeXAtom-ORD"><mi mathvariant="normal">F</mi></mrow><mo stretchy="false">→<!-- → --></mo></mover></mrow></mrow><mrow class="MJX-TeXAtom-ORD"><mn>3</mn></mrow></msub></mstyle></mrow><annotation encoding="application/x-tex">{\displaystyle {\vec {\mathrm {F} }}_{3}}</annotation></semantics></math></span><img src="https://wikimedia.org/api/rest_v1/media/math/render/svg/aeb569f095869edf7111b0ce19d3d903c789947b" class="mwe-math-fallback-image-inline" aria-hidden="true" style="vertical-align: -0.671ex; width:2.572ex; height:3.176ex;" alt="{\displaystyle {\vec {\mathrm {F} }}_{3}}"></span> and <span class="mwe-math-element"><span class="mwe-math-mathml-inline mwe-math-mathml-a11y" style="display: none;"><math xmlns="http://www.w3.org/1998/Math/MathML" alttext="{\displaystyle {\vec {\mathrm {F} }}_{4}}"><semantics><mrow class="MJX-TeXAtom-ORD"><mstyle displaystyle="true" scriptlevel="0"><msub><mrow class="MJX-TeXAtom-ORD"><mrow class="MJX-TeXAtom-ORD"><mover><mrow class="MJX-TeXAtom-ORD"><mi mathvariant="normal">F</mi></mrow><mo stretchy="false">→<!-- → --></mo></mover></mrow></mrow><mrow class="MJX-TeXAtom-ORD"><mn>4</mn></mrow></msub></mstyle></mrow><annotation encoding="application/x-tex">{\displaystyle {\vec {\mathrm {F} }}_{4}}</annotation></semantics></math></span><img src="https://wikimedia.org/api/rest_v1/media/math/render/svg/bb4dc01f5575419d37a82bbfba346dda3a9c950e" class="mwe-math-fallback-image-inline" aria-hidden="true" style="vertical-align: -0.671ex; width:2.572ex; height:3.176ex;" alt="{\displaystyle {\vec {\mathrm {F} }}_{4}}"></span>, represented by broken line arrows) are known.
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