1. What is a Semicircle Perimeter?

A semicircle is half of a circle. Its perimeter consists of the curved part (half the circumference of a full circle) plus the diameter (the straight edge).

2. How Does the Calculator Work?

The calculator uses the semicircle perimeter formula:

Where:

• \( P \) — Perimeter of the semicircle
• \( \pi \) — Mathematical constant (approximately 3.14159)
• \( r \) — Radius of the semicircle

Explanation: The formula combines half the circumference of a full circle (\( \pi r \)) with the diameter (\( 2r \)) to get the total perimeter.

3. Importance of Perimeter Calculation

Details: Calculating the perimeter of a semicircle is important in various fields including architecture, engineering, and design where curved structures are involved.

4. Using the Calculator

Tips: Enter the radius value in any consistent unit of measurement. The result will be in the same units. The radius must be a positive number.

5. Frequently Asked Questions (FAQ)

Q1: Is the perimeter of a semicircle half the perimeter of a full circle?
A: No, because the perimeter includes both the curved part and the straight diameter. It's more than half of a full circle's circumference.

Q2: What's the difference between circumference and perimeter for a semicircle?
A: For a semicircle, the perimeter includes both the curved part (half the circumference) and the straight diameter, while circumference typically refers only to the curved distance around a full circle.

Q3: Can I use this calculator for any unit of measurement?
A: Yes, as long as you're consistent with your units. If you enter radius in centimeters, the result will be in centimeters.

Q4: How accurate is the calculation?
A: The calculation uses the precise value of π available in PHP, providing results accurate to 4 decimal places.

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