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Interactive resource

Sphere: 4πr² Area and (4/3)πr³ Volume

Geometry. Interactive 3D sphere — change the radius to see surface area, volume, and scaling laws.

  • Sphere
  • Solid geometry
  • Volume

Overview

Both area and volume depend on radius. Double r and area ×4 while volume ×8 — visible in 3D.

Explanation

Surface area S = 4πr² and volume V = (4/3)πr³.
Scaling the radius by k scales area by k² and volume by k³.
Compare with cylinder and cone formulas.

How to use

  1. Open the sphere scene.
  2. Orbit the 3D view.
  3. Adjust radius r.
  4. Read surface area and volume.

Scaling question

If r doubles, by what factors do area and volume change?

Knowledge points

  • Sphere
  • Solid geometry
  • Volume

FAQ

How does this relate to cylinders and cones?

Compare with the cylinder–cone volume tool for shared πr² structure.

Is this tool free?

Yes. It runs in the browser with no install.

Good for class demos?

Yes — project it and ask what changes when you drag a parameter.

How do I write the formula afterward?

Open the equation editor or symbol sheet and copy a clean expression.

Try the interactive