Perimeter of a Sector Calculator

Calculate the perimeter of a circular sector using central angle and radius

Calculate Sector Perimeter

The angle subtended by the arc at the center of the circle

The distance from the center to the edge of the circle

Sector Calculation Results

0.000
Arc Length (cm)
0.000
Sector Perimeter (cm)
0.000
Sector Area (cm²)
0.0°
Central Angle

Calculation Details

Arc Length Formula: L = α × r = 0.0000 × 0.000 = 0.000 cm

Perimeter Formula: P = 2r + L = 2 × 0.000 + 0.000 = 0.000 cm

Sector Area Formula: A = ½ × α × r² = 0.5 × 0.0000 × 0.000 = 0.000 cm²

Sector Analysis

Example Calculation

Pizza Slice Example

Scenario: Calculate perimeter of a pizza slice

Central angle: 65° (typical pizza slice)

Radius: 9 cm (pizza radius)

Arc length calculation: Convert 65° to radians = 1.134 rad

Arc length: L = 1.134 × 9 = 10.21 cm

Perimeter Calculation

P = 2r + L

P = 2 × 9 + 10.21

P = 18 + 10.21

P = 28.21 cm

This matches the competitor's example perfectly!

Sector Components

α

Central Angle

The angle at the center

Measured in degrees or radians

r

Radius

Distance from center to edge

Forms two straight sides of sector

L

Arc Length

Curved side of the sector

Calculated as L = α × r

Formula Reference

Perimeter

P = 2r + L

P = 2r + αr

P = r(2 + α)

Arc Length

L = α × r

α must be in radians

Sector Area

A = ½ × α × r²

Bonus calculation

Understanding Sector Perimeter

What is a Sector?

A sector is a portion of a circle enclosed by two radii and an arc. Think of it like a slice of pie or pizza. The perimeter of a sector includes the two straight edges (radii) plus the curved edge (arc).

Real-World Applications

  • Architecture: Fan-shaped buildings and structures
  • Engineering: Gear teeth and mechanical parts
  • Statistics: Pie charts and data visualization
  • Food industry: Pizza slices and cake portions

Formula Breakdown

P = 2r + L

P = 2r + αr

  • P: Perimeter of the sector
  • r: Radius of the circle
  • L: Arc length (curved edge)
  • α: Central angle in radians
  • 2r: Two straight edges (radii)

Important: When using degrees, convert to radians: α(rad) = α(deg) × π/180

Step-by-Step Calculation

1

Convert Angle

Convert degrees to radians if needed

2

Calculate Arc

Find arc length: L = α × r

3

Add Components

Perimeter = 2r + L