1. What is the Circumference of a Circle?

Definition: The circumference is the distance around the edge of a circle.

Purpose: Calculating circumference is essential in geometry, engineering, and various real-world applications like construction and manufacturing.

2. How Does the Calculator Work?

The calculator uses the formula:

Where:

• \( C \) — Circumference (meters)
• \( \pi \) — Mathematical constant (~3.14159)
• \( r \) — Radius of the circle (meters)

Explanation: The circumference is calculated by multiplying twice the radius by π (pi).

3. Importance of Circumference Calculation

Details: Knowing the circumference helps in determining material requirements for circular objects, designing wheels, pipes, and other circular components.

4. Using the Calculator

Tips: Simply enter the radius of the circle in meters. The radius must be greater than 0.

5. Frequently Asked Questions (FAQ)

Q1: What if I know the diameter instead of radius?
A: The radius is half the diameter. Divide your diameter by 2 before entering.

Q2: Can I use different units?
A: Yes, as long as you're consistent. The result will be in the same units as your input.

Q3: How precise is the π value used?
A: The calculator uses PHP's built-in pi() function which provides sufficient precision for most practical applications.

Q4: What's the difference between circumference and perimeter?
A: Circumference is specifically for circles, while perimeter is used for polygons.

Q5: Can I calculate radius from circumference?
A: Yes, use the formula \( r = \frac{C}{2\pi} \).