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Calculate Length of a Spiral

Spiral Length Formula:

\[ L = \int_0^\theta \sqrt{r^2 + \left(\frac{dr}{d\varphi}\right)^2} d\varphi \]

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length units/rad
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1. What is Spiral Length?

The length of a spiral is calculated by integrating along its curve from the starting angle to the ending angle. This measurement is important in various engineering and design applications where spiral shapes are used.

2. How Does the Calculator Work?

The calculator uses the spiral length formula:

\[ L = \int_0^\theta \sqrt{r^2 + \left(\frac{dr}{d\varphi}\right)^2} d\varphi \]

Where:

Explanation: The formula integrates the infinitesimal arc length elements along the spiral path to compute the total length.

3. Importance of Spiral Length Calculation

Details: Calculating spiral length is crucial in mechanical engineering (springs), architecture (spiral staircases), and other applications where spiral components are used.

4. Using the Calculator

Tips: Enter the radius, rate of change of radius with angle, and the total angle in radians. All values must be valid (radius ≥ 0, angle ≥ 0).

5. Frequently Asked Questions (FAQ)

Q1: What if my spiral has a changing rate of expansion?
A: This calculator assumes constant dr/dφ. For variable rates, you would need a more complex integral or numerical solution.

Q2: Can I use degrees instead of radians?
A: The formula requires radians. Convert degrees to radians by multiplying by π/180.

Q3: What are typical applications of this calculation?
A: Spiral length calculations are used in designing springs, spiral staircases, roller coasters, and other spiral-shaped components.

Q4: How accurate is the numerical integration?
A: The calculator uses 1000 integration steps, which provides good accuracy for most practical purposes.

Q5: What if my spiral is three-dimensional?
A: This calculator is for 2D spirals. 3D spirals (helixes) require a different formula accounting for the z-axis component.

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