How to Compute the Volume of a Cone in C

Introduction

In this lab, you will learn how to compute the volume of a cone using C programming. The lab covers the step-by-step process, including reading the radius and height of the cone, and then applying the mathematical formula to calculate the volume. The final step involves printing the calculated volume. This lab aims to provide a practical understanding of geometry calculations using C, which is a valuable skill for various programming applications.

Read Radius and Height

In this step, you will learn how to read the radius and height of a cone using C programming. These input values are essential for calculating the cone's volume.

First, create a new C file to start your program:

cd ~/project
nano cone_volume.c

Now, add the following code to read the radius and height:

#include <stdio.h>
#include <math.h>

int main() {
    double radius, height;

    printf("Enter the radius of the cone: ");
    scanf("%lf", &radius);

    printf("Enter the height of the cone: ");
    scanf("%lf", &height);

    return 0;
}

Let's break down the code:

We use double to store decimal numbers for radius and height
printf() displays prompts for user input
scanf() reads the user's input for radius and height

Compile and run the program to test input:

gcc cone_volume.c -o cone_volume -lm
./cone_volume

Example output:

Enter the radius of the cone: 5
Enter the height of the cone: 10

Compute Volume = (1.0/3.0)PIr²*h

In this step, you will learn how to calculate the volume of a cone using the mathematical formula: Volume = (1/3) _ π _ r² * h.

Open the previous cone_volume.c file to add the volume calculation:

cd ~/project
nano cone_volume.c

Update the code with the volume calculation:

#include <stdio.h>
#include <math.h>

int main() {
    double radius, height, volume;
    const double PI = 3.14159265358979323846;

    printf("Enter the radius of the cone: ");
    scanf("%lf", &radius);

    printf("Enter the height of the cone: ");
    scanf("%lf", &height);

    volume = (1.0/3.0) * PI * pow(radius, 2) * height;

    return 0;
}

Key changes in the code:

Added volume variable to store the calculated result
Defined PI as a constant with high precision
Used pow(radius, 2) to calculate r²
Implemented the cone volume formula

Compile the program:

gcc cone_volume.c -o cone_volume -lm

Example calculation:

Radius = 5
Height = 10
Volume = (1/3) _ π _ 5² * 10 ≈ 261.80

Print the Volume

In this step, you will learn how to display the calculated cone volume to the user using formatted output in C.

Open the previous cone_volume.c file to add volume printing:

cd ~/project
nano cone_volume.c

Update the code to print the volume:

#include <stdio.h>
#include <math.h>

int main() {
    double radius, height, volume;
    const double PI = 3.14159265358979323846;

    printf("Enter the radius of the cone: ");
    scanf("%lf", &radius);

    printf("Enter the height of the cone: ");
    scanf("%lf", &height);

    volume = (1.0/3.0) * PI * pow(radius, 2) * height;

    printf("Cone Volume: %.2f cubic units\n", volume);

    return 0;
}

Key changes in the code:

Added printf() to display the volume
Used %.2f format specifier to show 2 decimal places
Added "cubic units" to clarify the measurement

Compile and run the program:

gcc cone_volume.c -o cone_volume -lm
./cone_volume

Example output:

Enter the radius of the cone: 5
Enter the height of the cone: 10
Cone Volume: 261.80 cubic units

Summary

In this lab, you will learn how to read the radius and height of a cone, and then calculate its volume using the formula: Volume = (1/3) _ π _ r² * h. First, you will prompt the user to enter the radius and height of the cone, and store these values in variables. Then, you will compute the volume using the given formula and the mathematical constant π. Finally, you will print the calculated volume.