According to the provided reference, finding the circumference of a cylinder involves using a specific formula related to its radius.
Calculating the Circumference of the Base
Based on the reference, the primary step in determining the circumference of a cylinder is focused on its circular base.
The reference explicitly states: "You need to find the circumference by using the formula 2 π r".
This formula is used to calculate the distance around the circular base of the cylinder.
- Circumference Formula:
C = 2 * π * r
Here's a breakdown of the components:
C: Represents the Circumference of the base circle.π(Pi): A fundamental mathematical constant, approximately equal to 3.14159.r: Denotes the radius of the cylinder's circular base (the distance from the center of the circle to any point on its edge).
Applying the Formula
To find the circumference of the cylinder's base, you only need the radius of that base.
- Example: If a cylinder has a base radius (
r) of 7 inches, the circumference (C) is calculated as:
C = 2 * π * 7 inches
C = 14π inches
Using the approximation for Pi (3.14159):
C ≈ 14 * 3.14159 inches
C ≈ 43.98226 inches
Further Calculation Mentioned in the Reference
The provided reference also describes a subsequent calculation building upon the circumference:
The reference continues by stating: "...and then multiply this by the height of the cylinder". This refers to multiplying the circumference (2 * π * r) by the cylinder's height (h).
The reference clarifies the result of this multiplication: "The formula for the side of the cylinder then becomes 2 π r h".
This resulting formula (2 * π * r * h) calculates the lateral surface area of the cylinder, which is the area of the curved rectangular "side" if you were to unroll it. The reference refers to this as the formula for the "side of the cylinder".
In summary, the circumference of a cylinder specifically refers to the circumference of its circular base, found using the formula 2πr. The reference further describes multiplying this value by the height to get the formula for the "side of the cylinder" (2πrh), which is the lateral surface area.
