C Programs

Share with a Friend

C Program: Surface Area of a Sphere

Introduction

A sphere is a perfectly round 3D solid object where every point on the surface is equidistant from the center.
Examples in real life include balls, bubbles, and planets.

The surface area of a sphere is the total area covering its outer surface.
The formula is:

Surface Area=4πr²

where

• r = radius of the sphere
• π (pi) ≈ 3.14159

C Program: Surface Area of a Sphere

#include <stdio.h>
#define PI 3.14159   // Define constant PI
 
int main() {
    float radius, surface_area;
 
    // Input radius
    printf("Enter the radius of the sphere: ");
    scanf("%f", &radius);
 
    // Calculate surface area
    surface_area = 4 * PI * radius * radius;
 
    // Display result
    printf("Surface Area of Sphere = %.2f\n", surface_area);
 
    return 0;
}
 

 
OUTPUT 1 :
Enter the radius of the sphere: 7
Surface Area of Sphere = 615.75

OUTPUT 2 :
Enter the radius of the sphere: 3.5
Surface Area of Sphere = 153.94

Explanation

1. The program asks for the radius of the sphere.
2. Formula applied: 4 × π × r².
3. PI is defined with #define for accuracy.
4. The result is printed with two decimal places.