1. What is the Semi Circle Perimeter Formula?

The semi circle perimeter formula calculates the total length around a semi-circular shape, which includes both the curved arc and the straight diameter. It provides the complete boundary measurement for half of a circle.

2. How Does the Calculator Work?

The calculator uses the semi circle perimeter formula:

Where:

• \( \pi \) — Mathematical constant approximately equal to 3.14159
• \( Radius \) — The radius of the semi circle

Explanation: The formula combines half the circumference of a full circle (π × Radius) plus the diameter length (2 × Radius) to get the total perimeter.

3. Importance of Perimeter Calculation

Details: Calculating the perimeter of a semi circle is essential in various fields including architecture, engineering, construction, and design where curved structures with straight edges are involved.

4. Using the Calculator

Tips: Enter the radius value in the specified unit. The radius must be a positive number greater than zero for accurate calculation.

5. Frequently Asked Questions (FAQ)

Q1: Why do we add 2 × Radius to π × Radius?
A: π × Radius gives the length of the curved arc (half circumference), while 2 × Radius adds the straight diameter, completing the full perimeter.

Q2: What units should I use for the radius?
A: Use consistent units (cm, m, inches, etc.). The result will be in the same units as the input radius.

Q3: Can this formula be used for partial circles?
A: This specific formula is designed for semi circles (exactly half a circle). For other circular segments, different formulas apply.

Q4: How accurate is the π value used?
A: The calculator uses PHP's built-in M_PI constant which provides high precision (approximately 3.1415926535898).

Q5: What if I have the diameter instead of radius?
A: Simply divide the diameter by 2 to get the radius before using this calculator.