Arc Length Calculator

Arc Length

Sector Area

Chord Length

How to Calculate Arc Length

Arc length s = r x theta (radians). For degrees: s = r x theta x pi/180. Sector area A = 0.5 x r^2 x theta.

Chord length c = 2r x sin(theta/2). Arc is always longer than chord except at angle 0.

Used in engineering (pulleys, gears), construction (curved walls, arches), and physics (circular motion).

Frequently Asked Questions

Arc length formula?

s = r x theta (radians). For degrees: s = r x theta x pi/180. Full circle = 2*pi*r.

Arc vs chord length?

Arc follows the curve; chord is straight between endpoints. Arc is always longer.

When to use radians?

Radians simplify formulas (s=r*theta). In calculus and physics, radians are standard.

Find radius from arc length?

r = s / theta. Divide arc length by central angle in radians.

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