Elliptic Integral for Arc Length:
From: | To: |
The arc length of an ellipse is calculated using an elliptic integral of the second kind. Unlike circles, ellipses don't have a simple closed-form solution for arc length, requiring numerical methods for calculation.
The calculator uses numerical integration to solve the elliptic integral:
Where:
Explanation: The calculator uses Simpson's rule for numerical integration, dividing the interval into 1000 steps for accurate results.
Details: Calculating arc lengths of ellipses is important in astronomy (planetary orbits), engineering (elliptical gears), and architecture (elliptical designs).
Tips: Enter eccentricity (0 for circle, approaching 1 for highly elongated), start and end angles in radians. Angles should be between 0 and 2π, with end angle greater than start angle.
Q1: Why can't we have an exact formula for ellipse arc length?
A: Unlike circles, ellipses lead to non-elementary integrals that cannot be expressed in terms of basic functions.
Q2: What's the range for eccentricity?
A: Eccentricity must be 0 ≤ e < 1. e=0 gives a circle, approaching 1 gives a very elongated ellipse.
Q3: How accurate is the numerical integration?
A: Using 1000 steps with Simpson's rule provides accuracy to about 6 decimal places for most cases.
Q4: Can I calculate the full perimeter?
A: Yes, set α=0 and β=2π. The complete elliptic integral of the second kind gives the perimeter.
Q5: What are practical applications?
A: Used in orbital mechanics, antenna design, architectural features, and mechanical engineering of elliptical components.