What is the Difference Between Diameter and Radius?

The difference between diameter and radius lies in their definitions and their relationship to the circle. Here are the key points:

• Diameter: The diameter is the longest line that can be drawn in a circle, passing through the center of the circle. It represents the full length of the circle running from the edge, through the midpoint, all the way to the other side.
• Radius: The radius is the line joining the center of the circle to any point on the circumference. It is the distance from the center of the circle to any point on the boundary.

The relationship between the diameter and radius is that the radius ($r$) is half of the diameter ($d$), represented by the formula: $$2r = d$$.

Some other important concepts related to circles include:

• Circumference: The distance around the boundary of a circle is called the circumference. The formula for calculating the circumference is $$C = \pi d$$ or $$C = 2\pi r$$.
• Chord: The line segment that joins two points on the circle is a chord. Every diameter is a chord, but not every chord is a diameter.
• Segment: The area that a chord cuts off is called a segment.
• Sector: The area inside a circle and bounded by two radii is a sector.
• Arc: The length between two points around the circumference of a circle is an arc.

Comparative Table: Diameter vs Radius

The main difference between diameter and radius lies in their definitions and measurements. Here is a table highlighting the differences:

In summary, the diameter is the entire length of the circle from one side to the other, while the radius is the distance from the edge of the circle to the center.