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Cone Slant Height Calculator

Cone Slant Height Formula:

\[ l = \sqrt{r^2 + h^2} \]

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1. What is Cone Slant Height?

The slant height (l) of a cone is the distance from the apex to any point on the edge of the circular base. It's an important measurement in geometry for calculating the lateral surface area and other properties of cones.

2. How Does the Calculator Work?

The calculator uses the slant height formula:

\[ l = \sqrt{r^2 + h^2} \]

Where:

Explanation: The formula is derived from the Pythagorean theorem, where the slant height forms the hypotenuse of a right triangle with the radius and height as the other two sides.

3. Importance of Slant Height Calculation

Details: Knowing the slant height is essential for calculating the lateral surface area of a cone (\( πrl \)), which is important in various engineering and architectural applications.

4. Using the Calculator

Tips: Enter the radius and height of the cone in the same length units. Both values must be positive numbers. The result will be in the same units as your input.

5. Frequently Asked Questions (FAQ)

Q1: What's the difference between height and slant height?
A: Height is the perpendicular distance from base to apex, while slant height is the diagonal distance along the cone's side.

Q2: Can I use this for truncated cones?
A: No, this formula is only for regular cones. Truncated cones (frustums) have a different formula for their slant height.

Q3: What units should I use?
A: Any consistent length units (cm, m, inches, etc.) can be used as long as both radius and height are in the same units.

Q4: How accurate is this calculation?
A: The calculation is mathematically exact for perfect right circular cones.

Q5: What if my cone isn't a right circular cone?
A: This formula only applies to right circular cones where the apex is directly above the center of the base.

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