1. Surface Area of Cylinders
Geometry
Surface Area of Cylinders

2. Surface Area
Cylinder – (circular prism) a prism with two parallel, equal circles on opposite sides.
To find the surface area of a cylinder we can add up the areas of the separate faces.

3. Surface Area
In a cylinder there are a pair of opposite and equal circles.
We can find the surface area of a cylinder by adding the areas of the two blue ends (A) and the yellow sides (B). A B

4. Surface Area
We can find the area of the two ends (A) by using the formula for the area of a circle.
A = π r2
Side
Area
Number of Sides
Total Area A B
Total
5cm A
8cm B

5. Surface Area
We can find the area of the two ends (A) by using the formula for the area of a circle.
A = π r2
Side
Area
Number of Sides
Total Area A
78.5 cm2 2
157 cm2 B
Total
5cm A
8cm B

6. Surface Area
If we “unwrapped” the cylinder, what shape would the outside “B” be?
Side
Area
Number of Sides
Total Area A
78.5 cm2 2
157 cm2 B
Total
5cm A
8cm B

7. Surface Area
“B” would be in the shape of a rectangle, with the height forming one side and the circumference of the top forming the second side.
Side
Area
Number of Sides
Total Area A
78.5 cm2 2
157 cm2 B
Total
5cm A
8cm B

8. A = 2πr * h Surface Area A = b * h A B A B Total Side Area Total Area
Number of Sides
Total Area A
78.5 cm2 2
157 cm2 B
Total
5cm A
8cm B

9. A = 2πr * h A = 2 (3.14) (5) * 8 Surface Area A B A B Total Side Area
Number of Sides
Total Area A
78.5 cm2 2
157 cm2 B
Total
5cm A
8cm B

10. A = 2πr * h A = 251.2 cm2 Surface Area A B A B Total Side Area
Number of Sides
Total Area A
78.5 cm2 2
157 cm2 B
251.2 cm2 1
Total
5cm A
8cm B

11. A = 2πr * h A = 251.2 cm2 Surface Area A B A B Total Side Area
Number of Sides
Total Area A
78.5 cm2 2
157 cm2 B
251.2 cm2 1
Total
408.2 cm2
5cm A
8cm B

12. Sketch cylinder and copy table. Work together to find the S.A.
Surface Area
Side
Area
Number Sides
Total Area

13. Surface Area Assignment A A
Sketch cylinder and copy table. Calculate S.A.
Side
Area
Number Sides
Total Area
4.1m A A
1.9m