Question

write a python program that accepts radius of a circle and prints it's area.

Answer 1

Area of a Circle is givem by:

$\sf Area = \pi\times radius^2$

So we have to take an input of the value of radius, compute the value of area and print it accordingly.

We need the value of $\pi$ too. We can set its value as 22/7 or 3.1416 approximately.

Or we can use the pi available in the math module.

Here is a sample program which accomplishes the task:

#Program to calculate Area of Circle

from math import pi

#Or we can set pi=3.1416 approximately

radius = float(input("Enter the radius: "))

area=pi*radius*radius

print("Area of the circle is",format(area,'.3f'),"sq units")

The format command with '.3f' rounds off the value of area to three decimal places.

A screenshot of the code along with its execution at the terminal is attached.

Answer 2

We know that, area of a circle is calculated as,

$A=\pi r^{2}$

Algorithm

Step 1: Begin.

Step 2: Take input radius, $r$ from user.

Step 3: Calculate area of circle using above formula.

Step 4: Print Area

Step 5: End.

Python program that takes a circle's radius and prints its area

from math import pi

r = float(input ("Enter radius of the circle : "))

print ("The area of the circle with radius " + str(r) + " is: " + str(pi * r**2))

#SPJ2