Sector Area Calculator
Sector Area
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Arc Length
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Sector Perimeter
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Calculating Sector Area
A = (1/2)r^2*theta (radians) or (theta/360)*pi*r^2 (degrees). Perimeter = 2r + arc length.
A 60-degree sector of radius 10 has area ~52.36 (one-sixth of circle). 180-degree = half circle area.
Used in land surveying, pie charts, fan design, and curved structures.
Frequently Asked Questions
Sector area formula?
A = (1/2)r^2*theta (radians) or (theta/360)*pi*r^2 (degrees).
Find angle from area?
theta = 2A/r^2 (radians) or theta = 360A/(pi*r^2) (degrees).
Sector perimeter?
P = 2r + arc = 2r + r*theta. Two radii plus the curved arc.
Sector vs segment?
Sector: bounded by two radii and arc (pie slice). Segment: bounded by chord and arc.