1. What is the Diameter of a Circle?

The diameter of a circle is the longest distance from one point on the circle to another, passing through the center. It is exactly twice the length of the radius.

2. How Does the Calculator Work?

The calculator uses the diameter formula:

Where:

• \( d \) — Diameter of the circle
• \( r \) — Radius of the circle

Explanation: The diameter is simply twice the length of the radius, as the radius extends from the center to the edge of the circle.

3. Importance of Diameter Calculation

Details: Knowing the diameter is essential for many geometric calculations including circumference, area, and in practical applications like engineering and construction.

4. Using the Calculator

Tips: Enter the radius in any length unit (meters, inches, feet, etc.). The result will be in the same units. The radius must be a positive number.

5. Frequently Asked Questions (FAQ)

Q1: What's the difference between diameter and radius?
A: The radius is half the diameter - it's the distance from the center to the edge, while diameter goes all the way across through the center.

Q2: Can I calculate diameter from circumference?
A: Yes, diameter = circumference / π (pi, approximately 3.14159).

Q3: What units should I use?
A: Any length units can be used (meters, inches, feet, etc.), just be consistent with your measurements.

Q4: Is diameter always twice the radius?
A: Yes, this is a fundamental property of circles in Euclidean geometry.

Q5: How precise should my radius measurement be?
A: The precision depends on your application. For most practical purposes, 2-3 decimal places are sufficient.