# Diagrams and math Example: resistance $R=100\,\Omega$ and voltage $V=10\,\mathrm{V}$. $$P=\frac{V^2}{R}=\frac{10^2}{100}=1\,\mathrm{W}$$ ```mermaid flowchart LR A[Set conditions] --> B[Calculate] --> C[Check specifications] classDef default fill:#FFFDF2,stroke:#385723,color:#385723 linkStyle default stroke:#385723 ``` | Voltage | Resistance | Power | | --- | --- | --- | | 5 V | 100 Ω | 0.25 W | | 10 V | 100 Ω | 1.00 W | ## Try it 1. Open a copy of this document in mdEditor. 2. Change the first heading to “Diagrams and math: reviewed”. Check the preview. 3. Change “Check specifications” in the diagram to “Verify by measurement”. The diagram shows the new label. 4. Select “Save” to save the Markdown, then “Save As” and choose PDF to export a PDF. 5. Open the PDF and check the heading, diagram, equation and table. Recalculate and update the equation and table yourself when changing the values; mdEditor does not calculate them. Actual component selection also requires checking temperature and derating.