Surface Area of Combination of Solids

Calculating Visible Curved Surfaces

Welcome! Learn how to calculate surface areas when solids combine.
🎯 Key Concept
Only Visible Surfaces Count!

When solids combine, hidden surfaces where they join are NOT included in total surface area.

📐 Formula Strategy
TSA = Σ Visible CSAs

Total Surface Area = Sum of all visible curved surface areas minus any hidden parts.

🔍 Common Formulas
Cylinder CSA: 2πrh
Cone CSA: πrl
Hemisphere CSA: 2πr²

Remember these for combined solids!

💡 Pro Tip
Visualize in 3D

Color-code visible surfaces to identify what gets painted or covered.