Finding the Length of the Common Chord

Oct 13, 2025 by wbrum.org 97 views

Introduction

In geometry, the problem of overlapping circles is a classic example of a complex problem that can be solved using various mathematical techniques. In this article, we will explore the problem of two circles of radius 12 that overlap such that each circle passes through the center of the other. Our goal is to find the length of the common chord, which is the dotted line that connects the two points of intersection between the two circles.

Understanding the Problem

To solve this problem, we need to understand the geometric properties of the overlapping circles. Since each circle passes through the center of the other, we can draw a line from the center of one circle to the center of the other. This line will be the perpendicular bisector of the common chord, and it will also be the line that passes through the point of intersection between the two circles.

Drawing the Diagram

Let's draw a diagram to visualize the problem. We will draw two circles, each with a radius of 12, and we will draw a line from the center of one circle to the center of the other. We will also draw the common chord, which is the dotted line that connects the two points of intersection between the two circles.

  +---------------+
  |               |
  |  Circle 1    |
  |               |
  +---------------+
           |
           |
           v
  +---------------+
  |               |
  |  Circle 2    |
  |               |
  +---------------+
           |
           |
           v
  +---------------+
  |               |
  |  Common Chord  |
  |               |
  +---------------+

Finding the Length of the Common Chord

To find the length of the common chord, we need to use the Pythagorean theorem. We can draw a right triangle with the common chord as the hypotenuse, and the radii of the two circles as the legs of the triangle. The length of the common chord will be the hypotenuse of this right triangle.

  +---------------+
  |               |
  |  Circle 1    |
  |               |
  +---------------+
           |
           |
           v
  +---------------+
  |               |
  |  Right Triangle  |
  |               |
  +---------------+
           |
           |
           v
  +---------------+
  |               |
  |  Circle 2    |
  |               |
  +---------------+

The length of the common chord can be found using the Pythagorean theorem:

  c^2 = a^2 + b^2

where c is the length of the common chord, and a and b are the radii of the two circles.

  c^2 = 12^2 + 12^2
  c^2 = 144 + 144
  c^2 = 288
  c = √288
  c = 12√2

Therefore, the length of the common chord is 12√2.

Conclusion

In this article, we have solved the problem of finding the length of the common chord of two overlapping circles. We have used the Pythagorean theorem to find the length of the common chord, and we have shown that it is equal to 12√2. This problem is a classic example of a complex problem that can be solved using various mathematical techniques, and it is a great exercise for students to practice their problem-solving skills.

Additional Resources

For more information on the Pythagorean theorem and its applications, please see the following resources:

References

Weisstein, Eric W. "Pythagorean Theorem." From MathWorld--A Wolfram Web Resource.
Khan Academy. "Geometry."
Math Open Reference. "Geometry."
Overlapping Circles: A Q&A Guide =====================================

Introduction

In our previous article, we explored the problem of finding the length of the common chord of two overlapping circles. In this article, we will answer some of the most frequently asked questions about overlapping circles and provide additional insights into this fascinating topic.

Q: What is the condition for two circles to overlap such that each circle passes through the center of the other?

A: For two circles to overlap such that each circle passes through the center of the other, the distance between the centers of the two circles must be equal to the sum of their radii.

Q: How do I draw a diagram to visualize the problem of overlapping circles?

A: To draw a diagram to visualize the problem of overlapping circles, you can start by drawing two circles with radii equal to the given values. Then, draw a line from the center of one circle to the center of the other. This line will be the perpendicular bisector of the common chord and will also pass through the point of intersection between the two circles.

Q: What is the relationship between the radii of the two circles and the length of the common chord?

A: The length of the common chord is equal to the square root of the sum of the squares of the radii of the two circles.

Q: Can I use the Pythagorean theorem to find the length of the common chord?

A: Yes, you can use the Pythagorean theorem to find the length of the common chord. The Pythagorean theorem states that the square of the length of the hypotenuse of a right triangle is equal to the sum of the squares of the lengths of the other two sides. In this case, the hypotenuse is the common chord, and the other two sides are the radii of the two circles.

Q: What is the formula for finding the length of the common chord?

A: The formula for finding the length of the common chord is:

c^2 = a^2 + b^2

where c is the length of the common chord, and a and b are the radii of the two circles.

Q: Can I use this formula to find the length of the common chord for any two circles?

A: Yes, you can use this formula to find the length of the common chord for any two circles, as long as the distance between the centers of the two circles is equal to the sum of their radii.

Q: What are some real-world applications of overlapping circles?

A: Overlapping circles have many real-world applications, including:

Geometry and trigonometry: Overlapping circles are used to study the properties of circles and their intersections.
Computer graphics: Overlapping circles are used to create realistic images and animations.
Engineering: Overlapping circles are used to design and analyze mechanical systems, such as gears and pulleys.
Physics: Overlapping circles are used to study the motion of objects and the behavior of physical systems.

Conclusion

In this article, we have answered some of the most frequently asked questions about overlapping circles and provided additional insights into this fascinating topic. We hope that this article has been helpful in understanding the properties of overlapping circles and their applications in various fields.

Additional Resources

For more information on overlapping circles and their applications, please see the following resources: