A rectangular sheet of paper, 44 cm × 20 cm, is rolled along its length to form a cylinder. Find the total surface area of the cylinder thus generated.
The rectangular sheet of paper $44 \mathrm{~cm} \times 20 \mathrm{~cm}$ is rolled along its length to form a cylinder. The height of the cylinder is $20 \mathrm{~cm}$ and circumference is $44 \mathrm{~cm}$.
We have:
Height, $h=20 \mathrm{~cm}$
Circumference $=2 \pi r=44 \mathrm{~cm}$
$\therefore$ Total surface area is $S=2 \pi r h$
$=44 \times 20 \mathrm{~cm}^{2}$
The rectangular sheet of paper $44 \mathrm{~cm} \times 20 \mathrm{~cm}$ is rolled along its length to form a cylinder. The height of the cylinder is $20 \mathrm{~cm}$ and circumference is $44 \mathrm{~cm}$.
We have:
Height, $h=20 \mathrm{~cm}$
Circumference $=2 \pi r=44 \mathrm{~cm}$
$\therefore$ Total surface area is $S=2 \pi r h$
$=44 \times 20 \mathrm{~cm}^{2}$
$=880 \mathrm{~cm}^{2}$