确定球面镜焦距的程序

编写程序以确定球面镜的焦距。
焦距是镜的中心到主要焦点之间的距离。为了确定球面镜的焦距，我们应该知道该镜的曲率半径。从顶点到曲率中心的距离称为曲率半径。
焦距是曲率半径的一半。
公式 ：

F =   ( R / 2 )      for concave mirror
F = - ( R / 2 )      for convex mirror

例子 ：

For a convex mirror
Input : R = 30 
Output : F = 15


For a convex mirror
Input : R = 25
Output : F = - 12.5

C++

// C++ program to determine
// the focal length of a
// of a spherical mirror
#include
using namespace std;
 
// Determines focal length
// of a spherical concave
// mirror
float focal_length_concave(float R)
{
    return R / 2 ;
}
 
// Determines focal length of a
// spherical convex mirror
float focal_length_convex(float R)
{
    return - ( R / 2 ) ;
}
 
// Driver function
int main()
{
    float R = 30 ;    
    cout << "Focal length of spherical"
         << "concave mirror is : "
         << focal_length_concave(R)
         << " units\n";
    cout << "Focal length of spherical"
         << "convex mirror is : "
         << focal_length_convex(R)
         << " units";
    return 0;
}

Java

// Java program to determine
// the focal length of a
// of a spherical mirror
import java.util.*;
import java.lang.*;
 
public class GfG{
    // Determines focal length
    // of a spherical concave
    // mirror
    public static float focal_length_concave(float R)
    {
        return R / 2 ;
    }
 
    // Determines focal length of a
    // spherical convex mirror
    public static float focal_length_convex(float R)
    {
        return - ( R / 2 ) ;
    }
     
    // Driver function
    public static void main(String argc[])
    {
        float R = 30 ;
         
        System.out.print("Focal length of" +
                         "spherical concave"+
                         "mirror is : "+
                         focal_length_concave(R) +
                         " units\n");
                         
        System.out.println("Focal length of"+
                           "spherical convex"+
                           "mirror is : "+
                           focal_length_convex(R) +
                           " units");
    }
}
 
/* This code is contributed by Sagar Shukla */

Python

# Python3 program to determine
# the focal length of a
# of a spherical mirrorr
 
# Determines focal length of
# a spherical concave mirror
def focal_length_concave(R):
    return R / 2
 
# Determines focal length of
# a spherical convex mirror
def focal_length_convex(R):
    return - ( R/ 2 )
 
# Driver function
R = 30 ;
print("Focal length of spherical concave mirror is :",
        focal_length_concave(R)," units")
print("Focal length of spherical convex mirror is : ",
        focal_length_convex(R)," units")

C#

// C# program to determine the focal
// length of a of a spherical mirror
using System;
 
class GfG {
     
    // Determines focal length of a
    // spherical concave mirror
    public static float focal_length_concave(float R)
    {
        return R / 2 ;
    }
 
    // Determines focal length of a
    // spherical convex mirror
    public static float focal_length_convex(float R)
    {
        return - ( R / 2 ) ;
    }
     
    // Driver function
    public static void Main(String[] argc)
    {
        float R = 30 ;
        Console.Write("Focal length of" +
                      "spherical concave" +
                      "mirror is : " +
                      focal_length_concave(R) +
                      " units\n");
                         
        Console.Write("Focal length of" +
                      "spherical convex" +
                      "mirror is : " +
                      focal_length_convex(R) +
                      " units");
    }
}
 
/* This code is contributed by parashar */

Javascript

 
// javascript program to determine
// the focal length of a
// of a spherical mirror
 
// Determines focal length
    // of a spherical concave
    // mirror
    function focal_length_concave(R)
    {
        return R / 2 ;
    }
   
    // Determines focal length of a
    // spherical convex mirror
    function focal_length_convex(R)
    {
        return - ( R / 2 ) ;
    }
 
// Driver Function
 
         let R = 30 ;
           
        document.write("Focal length of" +
                         "spherical concave"+
                         "mirror is : "+
                         focal_length_concave(R) +
                         " units" + "<br/>");
                           
        document.write("Focal length of"+
                           "spherical convex"+
                           "mirror is : "+
                           focal_length_convex(R) +
                           " units");
      
     // This code is contributed by susmitakundugoaldanga.

输出 ：

Focal length of spherical concave mirror is 15 units
Focal length of spherical convex mirror is -15 units