Area of a Ring or a Circular Washer (Circle Inside another Circle)There are many pages in this site explaining how to find the area of a circle. Now is the time to apply this information to solve word problems involving circles. In this presentation we will explore how to find the area of a ring or a circular washer. A circular washer consists of two concentric circles or circle inside a circle. Consider the following example: Find the area of a circular washer which have an inner radius of 3 cm and the outer radius of 5 cm, as shown in the image given below:
Area of smaller circle: Given radius for the smaller (inner) circle r = 3 cm Area of smaller circle = pi x radius x radius = 3.14 x 3 x 3 = 3.14 x 9 = 28.26 sq.cm Hence the area of the inner circle is 28.26 square centimeters. Area of larger circle: Given radius for the larger (outer) circle is R = 5 cm Area of the larger circle = Pi x radius x radius = 3.14 x 5 x 5 = 3.14 x 25 = 78.50 sq.cm Hence the area of the outer (larger) circle is 78.50 square centimeters.
Area of the washer: Once you have calculated the area of both the circles (inner and outer) using given radii, the next step is to find the area of the washer by subtracting the above results. The area of the washer is equal to the area between both the circles. Area of the washer = Area of outer circle - Area of the inner circle = 78.50 - 28.26 = 50.24 sq.cm Hence the area of the ring (circular washer) with outer radius of 5 cm and the inner radius of 3 cm found to be 50.24 sq. cm.
Worksheets on finding area of a ring or area of a circular washer worksheets: |
Circle Area Area Of A Circle Circle Basics Basics About A Circle Use of Pi Pi in Area of a Circle Formula Area of a Circle Formula Lessons Printable Lessons Area Using Radius Area Using Diameter Area & Circumference Radius From Area Diameter From Area Circle Inside A Square Square Inside A Circle Area Of A Ring Applications Word Problems About Us About Areacircle.com Privacy Policy Privacy Policy Terms Of Use |