1. What is Diameter?

The diameter is a straight line passing from side to side through the center of a circle or sphere. It is the longest chord of a circle and is exactly twice the length of the radius.

2. How to Calculate Diameter

The diameter can be calculated using two main formulas:

Where:

• \( D \) — Diameter (m)
• \( r \) — Radius (m)
• \( C \) — Circumference (m)
• \( \pi \) — Mathematical constant (approximately 3.14159)

Explanation: The diameter is directly proportional to both the radius and circumference of a circle. When you know the radius, simply multiply by 2. When you know the circumference, divide by π (pi).

3. Importance of Diameter Calculation

Details: Diameter calculations are fundamental in geometry, engineering, construction, and various scientific fields. They are essential for determining circle properties, calculating areas, and designing circular objects.

4. Using the Calculator

Tips: Select the calculation type (from radius or circumference), enter the corresponding value in meters, and click calculate. All values must be positive numbers.

5. Frequently Asked Questions (FAQ)

Q1: What is the difference between diameter and radius?
A: The diameter is twice the length of the radius. Radius extends from center to circumference, while diameter extends across the entire circle through the center.

Q2: Can I calculate diameter from area?
A: Yes, using the formula \( D = 2 \times \sqrt{\frac{A}{\pi}} \) where A is the area of the circle.

Q3: Why is π used in circumference calculations?
A: π (pi) is the ratio of a circle's circumference to its diameter, approximately 3.14159. It's a fundamental constant in circle geometry.

Q4: What units should I use for diameter?
A: Diameter should be in the same units as your radius or circumference measurements (meters, centimeters, inches, etc.).

Q5: Is diameter only for circles?
A: While primarily used for circles, diameter can also refer to the widest distance across other symmetrical shapes and three-dimensional objects like spheres.