CIRCUMFERENCE OF A CIRCLE
Definition of Pi: Mathematicians have established
that the relationship of the circumference to the diameter
of a circle is a constant called Pi and written Z. The
numerical value of this constant is approximately
3.141592653. For our purpose 3.1416 or simply 3.14
The formula for the circumference of a circle is
C = nD where C is the circumference and D is the
diameter since D = 2R where R is the radius, the
formula may be written C = 27cR.
Diameter of circle O is 4".
Compute the circumference.
Formula C = nD
C = 3.1416 X 4"
C = 12.5664
The size of flat sheet necessary to form pipe.
By formula the circumference of the end is nD. If this
were rolled out, the stretchout would be xD.
STRETCHOUT OF A RIGHT
The stretchout of a right circular cone will be a
portion of a circle whose radius (S) is equal to the slant
height of the cone.
STRETCHOUT OF ROUND OBJECTS
To determine how much of the circle will be re-
quired for the cone, you measure on the circumference
of this circle the circumference of a circle of radius R.
Diameter of the round pipe= D
Length of the round pipe= 1