How to find Volume and Surface Area of a Sphere using C#?

To find the volume and surface area of a sphere using C#, we need to apply mathematical formulas that use the sphere's radius. A sphere is a perfectly round three-dimensional object where every point on its surface is equidistant from its center.

Formulas

The mathematical formulas for a sphere are −

Surface Area = 4 × ? × r²
Volume = (4/3) × ? × r³

Where r is the radius of the sphere and ? (pi) is approximately 3.14159 or can be represented as 22/7.

Using Math.PI for Accurate Calculations

Example

using System;

public class SphereCalculator {
   public static void Main(string[] args) {
      double radius = 15;
      double surfaceArea, volume;

      // Calculate surface area using Math.PI
      surfaceArea = 4 * Math.PI * radius * radius;

      // Calculate volume using Math.PI
      volume = (4.0 / 3.0) * Math.PI * radius * radius * radius;

      Console.WriteLine("Radius of Sphere: " + radius);
      Console.WriteLine("Surface Area of Sphere: " + Math.Round(surfaceArea, 2));
      Console.WriteLine("Volume of Sphere: " + Math.Round(volume, 2));
   }
}

The output of the above code is −

Radius of Sphere: 15
Surface Area of Sphere: 2827.43
Volume of Sphere: 14137.17

Using Approximation (22/7) for Pi

Example

using System;

public class SphereWithApproximation {
   public static void Main(string[] args) {
      double radius = 15;
      double surfaceArea, volume;
      double pi = 22.0 / 7.0;

      // Calculate surface area using 22/7 approximation
      surfaceArea = 4 * pi * radius * radius;

      // Calculate volume using 22/7 approximation
      volume = (4.0 / 3.0) * pi * radius * radius * radius;

      Console.WriteLine("Using ? ? 22/7:");
      Console.WriteLine("Radius: " + radius);
      Console.WriteLine("Surface Area: " + Math.Round(surfaceArea, 2));
      Console.WriteLine("Volume: " + Math.Round(volume, 2));
   }
}

The output of the above code is −

Using ? ? 22/7:
Radius: 15
Surface Area: 2828.57
Volume: 14142.86

Interactive Sphere Calculator with Multiple Radii

Example

using System;

public class MultipleSpheres {
   public static void CalculateSphere(double radius) {
      double surfaceArea = 4 * Math.PI * Math.Pow(radius, 2);
      double volume = (4.0 / 3.0) * Math.PI * Math.Pow(radius, 3);
      
      Console.WriteLine($"Radius: {radius}");
      Console.WriteLine($"Surface Area: {Math.Round(surfaceArea, 2)}");
      Console.WriteLine($"Volume: {Math.Round(volume, 2)}");
      Console.WriteLine("---");
   }

   public static void Main(string[] args) {
      double[] radii = {5, 10, 15, 20};
      
      Console.WriteLine("Sphere Calculations:");
      Console.WriteLine("===================");
      
      foreach (double r in radii) {
         CalculateSphere(r);
      }
   }
}

The output of the above code is −

Sphere Calculations:
===================
Radius: 5
Surface Area: 314.16
Volume: 523.6
---
Radius: 10
Surface Area: 1256.64
Volume: 4188.79
---
Radius: 15
Surface Area: 2827.43
Volume: 14137.17
---
Radius: 20
Surface Area: 5026.55
Volume: 33510.32
---

Key Points

• Use Math.PI for more accurate calculations instead of 22/7 approximation.

• Use Math.Pow(radius, 2) or radius * radius for squaring the radius.

• Use Math.Round() to limit decimal places in the output for better readability.

• Surface area is measured in square units (e.g., cm²), while volume is measured in cubic units (e.g., cm³).

Conclusion

Calculating the volume and surface area of a sphere in C# requires applying the mathematical formulas using the radius value. Use Math.PI for precise calculations and Math.Round() to format the output appropriately.