1. What is Annulus Area?

An annulus is the region between two concentric circles. The area of an annulus is calculated as the difference between the areas of the outer and inner circles.

2. How Does the Calculator Work?

The calculator uses the annulus area formula:

Where:

• \( A \) — Area of the annulus
• \( R \) — Outer radius
• \( r \) — Inner radius
• \( \pi \) — Mathematical constant (approximately 3.14159)

Explanation: The formula calculates the difference between the area of the larger circle and the area of the smaller circle.

3. Importance of Annulus Calculation

Details: Annulus area calculations are important in various engineering, architectural, and manufacturing applications where ring-shaped objects are used, such as pipes, washers, and bearings.

4. Using the Calculator

Tips: Enter both outer and inner radius values in the same units. Ensure the outer radius is larger than the inner radius. All values must be positive numbers.

5. Frequently Asked Questions (FAQ)

Q1: What is an annulus?
A: An annulus is a ring-shaped object, the region lying between two concentric circles.

Q2: Can the inner radius be zero?
A: No, if the inner radius is zero, it becomes a solid circle, not an annulus.

Q3: What units should I use?
A: You can use any consistent units (cm, m, inches, etc.) as long as both radii are in the same units.

Q4: What if the outer radius is smaller than the inner radius?
A: This would result in a negative area, which is not physically possible for an annulus.

Q5: How accurate is the calculation?
A: The calculation uses the mathematical constant π with high precision, making the result as accurate as your input values.