Solved example to find
Surface Area of a Cylinder
if its
Radius and Height
is given
QUESTION: A salt container has the shape of a cylinder. The radius of the container is 1.5 inches and the height is 6 inches. What is the surface area of the container? Use π = 3.14.
SOLUTION:
The surface
area of a cylinder can be defined as the total space covered by the
flat surfaces of the bases of the cylinder and its curved
surface.
The
total surface area of the cylinder has two components –
1.
a curved surface area and
2.
two bases area.
If
the radius of the base of the cylinder is ‘r’ and the height of the cylinder is
‘h’, then
·
Curved Surface Area = 2πrh
·
Area of one base = πr²
·
Area of two bases = πr² + πr² = 2πr²
Total
Surface Area of a cylinder = 2πr² + 2πrh
Here,
r =
1.5 inches
h = 6
inches
π =
3.14
Put
values in the equation 1
Surface
Area of a cylinder = 2πr² + 2πrh
=2πr
(r + h)
=
2(3.14)(1.5)(1.5 + 6)
=
2(3.14)(1.5) (7.5)
=70.65
inches²
Thus, if a salt container has radius 1.5 inches and height 6 inches then its surface area is 70.65 inches²