A cylinder is a closed solid that has two parallel (circular) bases connected by a curved surface.
The height h is the perpendicular distance between the bases.
r of a cylinder is the radius of a base.
Pi (π) is the ratio of a circle’s circumference to its diameter (π = c/d). It is a mathematical constant, with a value of 3.14159…
The volumeof a cylinder with radius is the area of the base times the height .
V = B h
V=(π r²) h
The surface area of a cylinder is the number of square units it takes to cover all the surface of a cylinder.
A = p h + 2 b
p is the perimeter of the circle (equals to 2 π r)
A=2 π r h + 2 π r²
If you unroll a cylinder, its net is two circles and a parallelogram.
The area of each circle is π r².
The area of the parallelogram is (2 π r)(h) = 2 π r h
The surface area of a cylinder with height h and radius r is the area of the two bases plus the area of the curved surface (parallelogram).
A = 2 b + (perimeter) h
A= 2 (π r²) + (2 π r) h
2 π r is the perimeter (circumference of the circle), and h the height of the cylinder.
A= 2 π r² + 2 π r h