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Circumference of a Sector Calculator

Sector Perimeter Formula:

\[ C = \frac{\theta}{360} \times 2\pi r + 2r \]

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1. What is Sector Perimeter?

A sector perimeter is the total distance around a sector of a circle, which includes the arc length plus the two radii. It's commonly needed in geometry, engineering, and design applications.

2. How Does the Calculator Work?

The calculator uses the sector perimeter formula:

\[ C = \frac{\theta}{360} \times 2\pi r + 2r \]

Where:

Explanation: The formula calculates the arc length portion first (fraction of the full circumference based on the angle), then adds the lengths of the two radii.

3. Importance of Sector Calculations

Details: Sector perimeter calculations are essential in many practical applications including construction (calculating materials needed for curved sections), manufacturing (designing circular components), and physics (calculating rotational motion paths).

4. Using the Calculator

Tips: Enter the angle in degrees (between 0 and 360) and the radius in any consistent length unit. The result will be in the same units as the radius input.

5. Frequently Asked Questions (FAQ)

Q1: What's the difference between sector perimeter and arc length?
A: Arc length is just the curved portion, while sector perimeter includes the arc length plus the two straight radii.

Q2: What if my angle is in radians?
A: Convert radians to degrees first (1 radian = 180/π degrees) or use the radian formula: C = θr + 2r.

Q3: Can I use this for partial circles (θ > 360°)?
A: No, the angle must be between 0° and 360° for a proper sector. For multiple rotations, you'd need to adjust the calculation.

Q4: How precise is this calculation?
A: The calculation is mathematically exact, though practical measurements of angle and radius will affect real-world accuracy.

Q5: What's the perimeter for a semicircle?
A: For θ = 180°, the perimeter would be πr + 2r (half the circumference plus the diameter).

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