Input Data :
Radius = 8 in
Objective :
Find the area of circle.
Solution :
Area = πr2
= 3.14 x (8)2
= 3.14 x (64)
Area = 201.1429 in²
Area and circumference of circle calculator uses radius length of a circle, and calculates the perimeter and area of the circle.
It is an online Geometry tool requires radius length of a circle. Using this calculator, we will understand methods of how to find the perimeter and area of a circle.
It is necessary to follow the next steps:
A set of points in a plane equally distanced from a given point $O$ is a circle. The point $O$ is called the center of the circle.
The distance from the center of a circle to any point on the circle is called the radius of this circle.A radius of a circle must be a positive real number. The circle with a center $O$ and a radius $r$ is denoted by $c(O,r)$.
The distance around a circle is called the perimeter or circumference of the circle. It is usually denoted by $C$.
Calculating areas and circumferences of circles plays an important role in almost all field of science and real life. For instance, formula for circumference and area of a circle can be applied into geometry. They are used to explore many other formulas and mathematical equations. An arch length is a portion of the circumference of a circle.
The ratio of the length of an arc to the circumference is equal to the ratio of the measure of the arc to $360$ degrees. A sector of a circles is the region bounded by two radii of the circle and their intercepted arc.
Practice Problem 1:
A pizza is divided into $8$ equal pieces. The diameter of the pizza is $25$ centimeters. Find the area of one piece of pizza.
Practice Problem 2:
Given a tire with diameter of $100$ centimeters. How many revolutions does tire make while traveling $10$ kilometers?
The circle calculator, formula, example calculation (work with steps), real world problems and practice problems would be very useful for grade school students (K-12 education) to understand the concept of perimeter and area of circle. This concept can be of significance in geometry, to find the perimeter, area and volume of solids. Real life problems on circles involving arc length, sector of a circle, area and circumference are very common, so this concept can be of great importance of solving problems.