How to calculate the volume of a sphere using C programming language?

The volume of a sphere is the amount of space enclosed within the sphere. In C programming, we can calculate this using the mathematical formula for sphere volume.

Syntax

volume = (4.0/3.0) * ? * radius³

Where ? (pi) ? 3.14159 and radius is the distance from the center to any point on the sphere's surface.

Algorithm

Step 1: Enter radius of sphere at runtime
Step 2: Apply the formula to variable
        Volume = (4/3) * ? * radius³
Step 3: Print the volume
Step 4: Stop

Example 1: Basic Volume Calculation

This example calculates the volume of a sphere with a fixed radius −

#include <stdio.h>

int main() {
    float vol;
    int rad;
    rad = 20;
    vol = ((4.0f/3.0f) * (3.1415) * rad * rad * rad);
    printf("The volume of a sphere is %.2f<br>", vol);
    return 0;
}

The volume of a sphere is 33509.34

Example 2: Volume and Surface Area Calculator

This example calculates both volume and surface area with user input −

#include <stdio.h>
#define PI 3.14159

int main() {
    float rad;
    float area, vol;
    
    printf("Enter radius of the sphere: ");
    scanf("%f", &rad);
    
    area = 4 * PI * rad * rad;
    vol = (4.0/3.0) * PI * rad * rad * rad;
    
    printf("Surface area of sphere is: %.3f<br>", area);
    printf("Volume of sphere is: %.3f<br>", vol);
    
    return 0;
}

Enter radius of the sphere: 4
Surface area of sphere is: 201.062
Volume of sphere is: 268.083

Key Points

• Use float or double data types for accurate decimal calculations.
• Define PI as a constant for better precision: #define PI 3.14159
• The formula is: V = (4/3) × ? × r³
• Always use (4.0/3.0) instead of (4/3) to avoid integer division.

Conclusion

Calculating sphere volume in C involves applying the mathematical formula with proper data types. Using the constant PI and floating-point arithmetic ensures accurate results for geometric calculations.