"Circumference of a circle"

Circumference of a Circle

  • Definition: The circumference of a circle is the distance around the circle, often referred to as its perimeter.

  • Formula: The circumference (C) of a circle can be calculated using the following formula:
    C=2πrC = 2\pi r

    • Where:
    • $C$ = Circumference
    • $\pi$ = Pi, approximately 3.14159
    • $r$ = Radius of the circle
Example Calculation

  • Given: A circle with a radius of 14 mm.

    • Therefore, we can substitute the value of the radius into the formula:
      C=2π(14)C = 2 \pi (14)

  • Step-by-Step Calculation:

    1. Substitute the radius into the formula:
      C=2π⋅14C = 2\pi \cdot 14
    2. Simplifying gives:
      C=28πC = 28\pi

  • Approximation: To find the approximate numerical value:

    • Using a calculator, 28π28\pi can be computed as:
      C≈28⋅3.14159≈87.964C \approx 28 \cdot 3.14159 \approx 87.964 mm
    • Rounding to the nearest hundredth, the circumference is approximately 87.96 mm.
Important Notes
  • Units: Always ensure to include the appropriate units when calculating the circumference. In this case, it is in millimeters (mm).
  • Use of Calculators: It is common to use a scientific calculator to compute values involving $\pi$ for more accurate results.